feat: initial commit — local services (backend + manager dashboard + waiter PWA)

Includes all work to date:
- local_backend: FastAPI backend with products, orders, tables, shifts, cloud sync
- manager_dashboard: React manager UI with product/category management, reports, settings
- waiter_pwa: React PWA for waiter devices
- Category reparent endpoint and UI
- Waiter domain: local_ip sent on heartbeat, waiter_domain persisted from cloud response
- QR code modal in AppInfoTab for waiter domain
- Product form: number input spinners removed, category pre-selected on new product
- Category row: count badge moved to far right

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

local_backend/models/business_day.py

@@ -0,0 +1,24 @@
+from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Text
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class BusinessDay(Base):
+    __tablename__ = "business_days"
+
+    id = Column(Integer, primary_key=True, index=True)
+    status = Column(String, default="open", nullable=False)  # 'open' | 'closed'
+    opened_at = Column(DateTime(timezone=True), default=_utcnow, nullable=False)
+    opened_by_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    closed_at = Column(DateTime(timezone=True), nullable=True)
+    closed_by_id = Column(Integer, ForeignKey("users.id"), nullable=True)
+    notes = Column(Text, nullable=True)
+
+    opener = relationship("User", foreign_keys=[opened_by_id])
+    closer = relationship("User", foreign_keys=[closed_by_id])
+    shifts = relationship("WaiterShift", back_populates="business_day")

local_backend/models/flag.py

@@ -0,0 +1,38 @@
+from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Boolean
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class TableFlagDef(Base):
+    """Manager-configurable flag definitions (name, emoji, color)."""
+    __tablename__ = "table_flag_defs"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False)
+    emoji = Column(String, nullable=True)
+    color = Column(String, nullable=True, default="#6b7280")  # hex background
+    text_color = Column(String, nullable=True, default=None)  # hex text; None = white
+    sort_order = Column(Integer, default=0, nullable=False)
+    is_active = Column(Boolean, default=True, nullable=False)
+    created_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    assignments = relationship("TableFlagAssignment", back_populates="flag_def", cascade="all, delete-orphan")
+
+
+class TableFlagAssignment(Base):
+    """Active flag on a specific table."""
+    __tablename__ = "table_flag_assignments"
+
+    id = Column(Integer, primary_key=True, index=True)
+    table_id = Column(Integer, ForeignKey("tables.id"), nullable=False)
+    flag_id = Column(Integer, ForeignKey("table_flag_defs.id"), nullable=False)
+    assigned_at = Column(DateTime(timezone=True), default=_utcnow)
+    assigned_by = Column(Integer, ForeignKey("users.id"), nullable=True)
+
+    flag_def = relationship("TableFlagDef", back_populates="assignments")
+    assigned_by_user = relationship("User")

local_backend/models/message.py

@@ -0,0 +1,48 @@
+from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Text, Boolean
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class QuickMessageTemplate(Base):
+    """Manager-configurable quick message templates."""
+    __tablename__ = "quick_message_templates"
+
+    id = Column(Integer, primary_key=True, index=True)
+    body = Column(String, nullable=False)
+    sort_order = Column(Integer, default=0, nullable=False)
+    is_active = Column(Boolean, default=True, nullable=False)
+    created_at = Column(DateTime(timezone=True), default=_utcnow)
+
+
+class StaffMessage(Base):
+    """A message sent from a manager to one or more waiters."""
+    __tablename__ = "staff_messages"
+
+    id = Column(Integer, primary_key=True, index=True)
+    sender_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    body = Column(Text, nullable=False)
+    # JSON arrays stored as text: "[1,2,3]" for waiter ids, "[5,6]" for table ids
+    target_waiter_ids = Column(Text, nullable=False, default="[]")
+    table_ids = Column(Text, nullable=False, default="[]")
+    created_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    sender = relationship("User", foreign_keys=[sender_id])
+    acks = relationship("StaffMessageAck", back_populates="message", cascade="all, delete-orphan")
+
+
+class StaffMessageAck(Base):
+    """Acknowledgement by a specific waiter for a specific message."""
+    __tablename__ = "staff_message_acks"
+
+    id = Column(Integer, primary_key=True, index=True)
+    message_id = Column(Integer, ForeignKey("staff_messages.id"), nullable=False)
+    waiter_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    acked_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    message = relationship("StaffMessage", back_populates="acks")
+    waiter = relationship("User")

local_backend/models/order.py

@@ -0,0 +1,131 @@
+from sqlalchemy import Column, Integer, String, Boolean, Float, DateTime, ForeignKey, Text
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class Order(Base):
+    __tablename__ = "orders"
+
+    id = Column(Integer, primary_key=True, index=True)
+    table_id = Column(Integer, ForeignKey("tables.id"), nullable=False)
+    opened_by = Column(Integer, ForeignKey("users.id"), nullable=False)
+    opened_at = Column(DateTime(timezone=True), default=_utcnow)
+    status = Column(String, default="open", nullable=False)  # open|partially_paid|paid|closed|cancelled
+    closed_at = Column(DateTime, nullable=True)
+    closed_by = Column(Integer, ForeignKey("users.id"), nullable=True)
+    notes = Column(Text, nullable=True)
+    business_day_id = Column(Integer, ForeignKey("business_days.id"), nullable=True)
+
+    table = relationship("Table", back_populates="orders")
+    opener = relationship("User", foreign_keys=[opened_by], back_populates="orders_opened")
+    closer = relationship("User", foreign_keys=[closed_by], back_populates="orders_closed")
+    items = relationship("OrderItem", back_populates="order", cascade="all, delete-orphan")
+    waiters = relationship("OrderWaiter", back_populates="order", cascade="all, delete-orphan")
+    print_logs = relationship("PrintLog", back_populates="order", cascade="all, delete-orphan")
+    audit_logs = relationship("OrderAuditLog", back_populates="order", cascade="all, delete-orphan")
+    discounts = relationship("OrderDiscount", back_populates="order", cascade="all, delete-orphan")
+
+
+class OrderWaiter(Base):
+    __tablename__ = "order_waiters"
+
+    id = Column(Integer, primary_key=True, index=True)
+    order_id = Column(Integer, ForeignKey("orders.id"), nullable=False)
+    waiter_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    assigned_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    order = relationship("Order", back_populates="waiters")
+    waiter = relationship("User", back_populates="order_assignments")
+
+
+class OrderItem(Base):
+    __tablename__ = "order_items"
+
+    id = Column(Integer, primary_key=True, index=True)
+    order_id = Column(Integer, ForeignKey("orders.id"), nullable=False)
+    product_id = Column(Integer, ForeignKey("products.id"), nullable=False)
+    added_by = Column(Integer, ForeignKey("users.id"), nullable=False)
+    quantity = Column(Integer, nullable=False)
+    unit_price = Column(Float, nullable=False)  # price snapshot at time of order
+    selected_options = Column(Text, nullable=True)    # JSON array of option ids
+    removed_ingredients = Column(Text, nullable=True) # JSON array of ingredient ids
+    notes = Column(Text, nullable=True)
+    status = Column(String, default="active", nullable=False)  # active|paid|cancelled
+    added_at = Column(DateTime(timezone=True), default=_utcnow)
+    printed = Column(Boolean, default=False, nullable=False)
+
+    # Payment tracking
+    paid_by = Column(Integer, ForeignKey("users.id"), nullable=True)
+    paid_at = Column(DateTime, nullable=True)
+    payment_method = Column(String, nullable=True)  # 'cash'|'card'|'other' — future use
+    paid_in_shift_id = Column(Integer, ForeignKey("waiter_shifts.id"), nullable=True)
+
+    order = relationship("Order", back_populates="items")
+    product = relationship("Product", back_populates="order_items")
+    added_by_user = relationship("User", foreign_keys=[added_by], back_populates="order_items")
+    paid_by_user = relationship("User", foreign_keys=[paid_by], back_populates="items_paid")
+
+
+class PrintLog(Base):
+    __tablename__ = "print_log"
+
+    id = Column(Integer, primary_key=True, index=True)
+    order_id = Column(Integer, ForeignKey("orders.id"), nullable=False)
+    printer_id = Column(Integer, ForeignKey("printers.id"), nullable=False)
+    printed_at = Column(DateTime(timezone=True), default=_utcnow)
+    item_ids = Column(Text, nullable=False)  # JSON array of order_item ids
+    success = Column(Boolean, nullable=False)
+    error_message = Column(Text, nullable=True)
+
+    order = relationship("Order", back_populates="print_logs")
+    printer = relationship("Printer", back_populates="print_logs")
+
+
+class OrderAuditLog(Base):
+    """Immutable append-only audit trail for every action on an order."""
+    __tablename__ = "order_audit_log"
+
+    id = Column(Integer, primary_key=True, index=True)
+    order_id = Column(Integer, ForeignKey("orders.id"), nullable=False)
+    event_type = Column(String, nullable=False)
+    # ORDER_OPENED | ITEMS_ADDED | PAYMENT | PAYMENT_OFFLINE | ORDER_CLOSED | ORDER_CANCELLED | ITEM_CANCELLED
+    waiter_id = Column(Integer, ForeignKey("users.id"), nullable=True)
+    item_ids = Column(Text, nullable=True)      # JSON list of OrderItem ids
+    amount = Column(Float, nullable=True)       # total value for PAYMENT events
+    payment_method = Column(String, nullable=True)
+    note = Column(Text, nullable=True)
+    created_at = Column(DateTime(timezone=True), default=_utcnow)
+    # Emergency offline payment fields
+    offline_uuid = Column(String, nullable=True)   # client-generated UUID for dedup
+    offline_at = Column(String, nullable=True)     # ISO timestamp from client
+    is_duplicate = Column(Integer, nullable=False, default=0)  # 1 = duplicate payment flagged
+
+    order = relationship("Order", back_populates="audit_logs")
+    waiter = relationship("User")
+
+    @property
+    def waiter_name(self):
+        return self.waiter.username if self.waiter else None
+
+
+class OrderDiscount(Base):
+    """Records a discount applied to an order or a specific item."""
+    __tablename__ = "order_discounts"
+
+    id = Column(Integer, primary_key=True, index=True)
+    order_id = Column(Integer, ForeignKey("orders.id"), nullable=False)
+    item_id = Column(Integer, ForeignKey("order_items.id"), nullable=True)  # NULL = whole-order discount
+    discount_type = Column(String, nullable=False)   # 'percent' | 'fixed'
+    discount_value = Column(Float, nullable=False)   # e.g. 10.0 = 10% or €10.00
+    applied_by = Column(Integer, ForeignKey("users.id"), nullable=False)
+    applied_at = Column(DateTime(timezone=True), default=_utcnow)
+    reason = Column(Text, nullable=True)
+
+    order = relationship("Order", back_populates="discounts")
+    item = relationship("OrderItem")
+    applied_by_user = relationship("User")

local_backend/models/printer.py

@@ -0,0 +1,17 @@
+from sqlalchemy import Column, Integer, String, Boolean
+from sqlalchemy.orm import relationship
+from database import Base
+
+
+class Printer(Base):
+    __tablename__ = "printers"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False)
+    ip_address = Column(String, nullable=False)
+    port = Column(Integer, default=9100, nullable=False)
+    is_active = Column(Boolean, default=True, nullable=False)
+    protocol = Column(String, default="escpos_tcp", nullable=False)
+
+    products = relationship("Product", back_populates="printer_zone")
+    print_logs = relationship("PrintLog", back_populates="printer")

local_backend/models/product.py

@@ -0,0 +1,123 @@
+from sqlalchemy import Column, Integer, String, Boolean, Float, ForeignKey, Text
+from sqlalchemy.orm import relationship
+from database import Base
+
+
+class Category(Base):
+    __tablename__ = "categories"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False)
+    color = Column(String, nullable=True)
+    sort_order = Column(Integer, default=0)
+    # self-referential: null = top-level, non-null = sub-category of parent
+    parent_id = Column(Integer, ForeignKey("categories.id"), nullable=True)
+    # position of the "General" group (direct products) among sub-categories
+    general_sort_order = Column(Integer, default=0, nullable=False)
+    # sub-categories only: if True, the accordion section is expanded by default on the PWA
+    auto_expanded = Column(Boolean, default=False, nullable=False)
+
+    products = relationship("Product", back_populates="category")
+    subcategories = relationship("Category", back_populates="parent", foreign_keys="Category.parent_id")
+    parent = relationship("Category", back_populates="subcategories", remote_side="Category.id", foreign_keys="Category.parent_id")
+
+
+class Product(Base):
+    __tablename__ = "products"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False)
+    category_id = Column(Integer, ForeignKey("categories.id"), nullable=True)
+    base_price = Column(Float, nullable=False)
+    is_available = Column(Boolean, default=True, nullable=False)
+    # "active" | "archived" — archived products are kept for order history but hidden from active use
+    lifecycle_status = Column(String, default="active", nullable=False)
+    printer_zone_id = Column(Integer, ForeignKey("printers.id"), nullable=True)
+    image_url = Column(String, nullable=True)
+    sort_order = Column(Integer, default=0, nullable=False)
+
+    category = relationship("Category", back_populates="products")
+    printer_zone = relationship("Printer", back_populates="products")
+    quick_options = relationship("ProductQuickOption", back_populates="product", cascade="all, delete-orphan")
+    options = relationship("ProductOption", back_populates="product", cascade="all, delete-orphan")
+    ingredients = relationship("ProductIngredient", back_populates="product", cascade="all, delete-orphan")
+    preference_sets = relationship("ProductPreferenceSet", back_populates="product", cascade="all, delete-orphan")
+    order_items = relationship("OrderItem", back_populates="product")
+
+
+class ProductOption(Base):
+    __tablename__ = "product_options"
+
+    id = Column(Integer, primary_key=True, index=True)
+    product_id = Column(Integer, ForeignKey("products.id"), nullable=False)
+    name = Column(String, nullable=False)
+    extra_cost = Column(Float, default=0.0)
+    allow_multiple = Column(Boolean, default=False, nullable=False)
+    # JSON array [{name, extra_cost, is_default}] — sub-options shown when this option is checked
+    sub_choices = Column(Text, nullable=True)
+    is_favorite = Column(Boolean, default=False, nullable=False)
+    favorite_sort_order = Column(Integer, default=0, nullable=False)
+
+    product = relationship("Product", back_populates="options")
+
+
+class ProductQuickOption(Base):
+    __tablename__ = "product_quick_options"
+
+    id = Column(Integer, primary_key=True, index=True)
+    product_id = Column(Integer, ForeignKey("products.id"), nullable=False)
+    name = Column(String, nullable=False)
+    price = Column(Float, default=0.0, nullable=False)
+    allow_multiple = Column(Boolean, default=False, nullable=False)
+    sort_order = Column(Integer, default=0, nullable=False)
+    is_favorite = Column(Boolean, default=False, nullable=False)
+    favorite_sort_order = Column(Integer, default=0, nullable=False)
+    is_compact = Column(Boolean, default=False, nullable=False)
+
+    product = relationship("Product", back_populates="quick_options")
+
+
+class ProductIngredient(Base):
+    __tablename__ = "product_ingredients"
+
+    id = Column(Integer, primary_key=True, index=True)
+    product_id = Column(Integer, ForeignKey("products.id"), nullable=False)
+    name = Column(String, nullable=False)
+    extra_cost = Column(Float, default=0.0)
+    is_favorite = Column(Boolean, default=False, nullable=False)
+    favorite_sort_order = Column(Integer, default=0, nullable=False)
+
+    product = relationship("Product", back_populates="ingredients")
+
+
+class ProductPreferenceSet(Base):
+    __tablename__ = "product_preference_sets"
+
+    id = Column(Integer, primary_key=True, index=True)
+    product_id = Column(Integer, ForeignKey("products.id"), nullable=False)
+    name = Column(String, nullable=False)
+    default_choice_id = Column(Integer, nullable=True)
+    # JSON: {name, default_choice_index, choices:[{name,extra_cost,is_default}]}
+    # Shared sub-set shown for all choices that don't have disables_subset=True
+    shared_subset = Column(Text, nullable=True)
+    is_favorite = Column(Boolean, default=False, nullable=False)
+    favorite_sort_order = Column(Integer, default=0, nullable=False)
+
+    product = relationship("Product", back_populates="preference_sets")
+    choices = relationship("ProductPreferenceChoice", back_populates="set", cascade="all, delete-orphan")
+
+
+class ProductPreferenceChoice(Base):
+    __tablename__ = "product_preference_choices"
+
+    id = Column(Integer, primary_key=True, index=True)
+    set_id = Column(Integer, ForeignKey("product_preference_sets.id"), nullable=False)
+    name = Column(String, nullable=False)
+    extra_cost = Column(Float, default=0.0)
+    # JSON array of sub-choice objects: [{name, extra_cost, is_default}]
+    # Per-choice inline sub-preference shown only when this choice is selected.
+    sub_choices = Column(Text, nullable=True)
+    # When True this choice hides the set-level shared_subset on the PWA.
+    disables_subset = Column(Boolean, default=False, nullable=False)
+
+    set = relationship("ProductPreferenceSet", back_populates="choices")

local_backend/models/settings.py

@@ -0,0 +1,19 @@
+from sqlalchemy import Column, Integer, String, DateTime, ForeignKey
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class PosSettings(Base):
+    __tablename__ = "pos_settings"
+
+    key = Column(String, primary_key=True)
+    value = Column(String, nullable=False)
+    updated_at = Column(DateTime(timezone=True), default=_utcnow, onupdate=_utcnow, nullable=False)
+    updated_by_id = Column(Integer, ForeignKey("users.id"), nullable=True)
+
+    updated_by = relationship("User", foreign_keys=[updated_by_id])

local_backend/models/shift.py

@@ -0,0 +1,36 @@
+from sqlalchemy import Column, Integer, Float, DateTime, ForeignKey, Text
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class WaiterShift(Base):
+    __tablename__ = "waiter_shifts"
+
+    id = Column(Integer, primary_key=True, index=True)
+    waiter_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    business_day_id = Column(Integer, ForeignKey("business_days.id"), nullable=False)
+    started_at = Column(DateTime(timezone=True), default=_utcnow, nullable=False)
+    ended_at = Column(DateTime(timezone=True), nullable=True)
+    starting_cash = Column(Float, nullable=True)
+    total_collected = Column(Float, nullable=True)  # snapshot written at shift end
+    notes = Column(Text, nullable=True)
+
+    waiter = relationship("User", foreign_keys=[waiter_id])
+    business_day = relationship("BusinessDay", back_populates="shifts")
+    breaks = relationship("ShiftBreak", back_populates="shift", cascade="all, delete-orphan")
+
+
+class ShiftBreak(Base):
+    __tablename__ = "shift_breaks"
+
+    id = Column(Integer, primary_key=True, index=True)
+    shift_id = Column(Integer, ForeignKey("waiter_shifts.id"), nullable=False)
+    started_at = Column(DateTime(timezone=True), default=_utcnow, nullable=False)
+    ended_at = Column(DateTime(timezone=True), nullable=True)
+
+    shift = relationship("WaiterShift", back_populates="breaks")

local_backend/models/table.py

@@ -0,0 +1,31 @@
+from sqlalchemy import Column, Integer, String, Boolean, Float, ForeignKey
+from sqlalchemy.orm import relationship
+from database import Base
+
+
+class TableGroup(Base):
+    __tablename__ = "table_groups"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False, unique=True)
+    prefix = Column(String, nullable=True)
+    sort_order = Column(Integer, default=0)
+    color = Column(String, nullable=True)
+
+    tables = relationship("Table", back_populates="group")
+    waiter_zones = relationship("WaiterZone", back_populates="group")
+
+
+class Table(Base):
+    __tablename__ = "tables"
+
+    id = Column(Integer, primary_key=True, index=True)
+    number = Column(Integer, nullable=False)
+    label = Column(String, nullable=True)
+    group_id = Column(Integer, ForeignKey("table_groups.id"), nullable=True)
+    is_active = Column(Boolean, default=True, nullable=False)
+    floor_x = Column(Float, nullable=True)
+    floor_y = Column(Float, nullable=True)
+
+    group = relationship("TableGroup", back_populates="tables")
+    orders = relationship("Order", back_populates="table")

local_backend/models/user.py

@@ -0,0 +1,70 @@
+from sqlalchemy import Column, Integer, String, Boolean, DateTime, ForeignKey
+from sqlalchemy.orm import relationship
+from datetime import datetime, timezone
+from database import Base
+
+
+def _utcnow():
+    return datetime.now(timezone.utc)
+
+
+class User(Base):
+    __tablename__ = "users"
+
+    id = Column(Integer, primary_key=True, index=True)
+    username = Column(String, unique=True, nullable=False, index=True)
+    pin_hash = Column(String, nullable=False)
+    password_hash = Column(String, nullable=True)
+    email = Column(String, nullable=True)
+    role = Column(String, nullable=False)  # 'waiter' | 'manager' | 'sysadmin'
+    is_active = Column(Boolean, default=True, nullable=False)
+    full_name = Column(String, nullable=True)
+    nickname = Column(String, nullable=True)
+    mobile_phone = Column(String, nullable=True)
+    avatar_url = Column(String, nullable=True)
+    created_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    orders_opened = relationship("Order", foreign_keys="Order.opened_by", back_populates="opener")
+    orders_closed = relationship("Order", foreign_keys="Order.closed_by", back_populates="closer")
+    order_items = relationship("OrderItem", foreign_keys="OrderItem.added_by", back_populates="added_by_user")
+    items_paid = relationship("OrderItem", foreign_keys="OrderItem.paid_by", back_populates="paid_by_user")
+    order_assignments = relationship("OrderWaiter", back_populates="waiter")
+    zone_assignments = relationship("WaiterZone", back_populates="waiter", cascade="all, delete-orphan")
+
+    primary_assignments = relationship(
+        "AssistantAssignment",
+        foreign_keys="AssistantAssignment.primary_waiter_id",
+        back_populates="primary_waiter",
+    )
+    assistant_assignments = relationship(
+        "AssistantAssignment",
+        foreign_keys="AssistantAssignment.assistant_waiter_id",
+        back_populates="assistant_waiter",
+    )
+
+
+class WaiterZone(Base):
+    """Maps a waiter to a table group they are allowed to operate in.
+    If a waiter has NO rows here, they see NOTHING.
+    A sentinel row with group_id=NULL means 'all zones'."""
+    __tablename__ = "waiter_zones"
+
+    id = Column(Integer, primary_key=True, index=True)
+    waiter_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    group_id = Column(Integer, ForeignKey("table_groups.id"), nullable=True)  # NULL = all zones
+    assigned_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    waiter = relationship("User", back_populates="zone_assignments")
+    group = relationship("TableGroup", back_populates="waiter_zones")
+
+
+class AssistantAssignment(Base):
+    __tablename__ = "assistant_assignments"
+
+    id = Column(Integer, primary_key=True, index=True)
+    primary_waiter_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    assistant_waiter_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    assigned_at = Column(DateTime(timezone=True), default=_utcnow)
+
+    primary_waiter = relationship("User", foreign_keys=[primary_waiter_id], back_populates="primary_assignments")
+    assistant_waiter = relationship("User", foreign_keys=[assistant_waiter_id], back_populates="assistant_assignments")