Initial Switch to V2. Completely Overhauled Backend, Frontend and General Structure.

backend/crm/service.py

@@ -305,6 +305,33 @@ async def get_last_comm_timestamp(customer_id: str) -> str | None:
     return None
 
 
+async def get_latest_comm_batch(customer_ids: list[str]) -> dict[str, dict]:
+    """Return a dict of customer_id → {id, type, occurred_at} for the latest comm per customer.
+    Uses a single SQL query — no N+1 regardless of list size.
+    """
+    if not customer_ids:
+        return {}
+    db = await mqtt_db.get_db()
+    placeholders = ",".join("?" * len(customer_ids))
+    rows = await db.execute_fetchall(
+        f"""
+        SELECT customer_id, id, type, COALESCE(occurred_at, created_at) AS ts
+        FROM crm_comms_log
+        WHERE customer_id IN ({placeholders})
+        AND customer_id IS NOT NULL AND customer_id != ''
+        ORDER BY ts DESC
+        """,
+        customer_ids,
+    )
+    # Keep only the first (latest) row per customer
+    result: dict[str, dict] = {}
+    for row in rows:
+        cid = row[0]
+        if cid not in result:
+            result[cid] = {"id": row[1], "type": row[2], "occurred_at": row[3]}
+    return result
+
+
 async def list_customers_sorted_by_latest_comm(customers: list[CustomerInDB]) -> list[CustomerInDB]:
     """Re-sort a list of customers so those with the most recent comm come first."""
     timestamps = await asyncio.gather(