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>

manager_dashboard/src/index.css

@@ -0,0 +1,36 @@
+@tailwind base;
+@tailwind components;
+@tailwind utilities;
+
+@layer base {
+  body {
+    @apply bg-slate-50 text-slate-900 text-base antialiased;
+  }
+}
+
+@layer components {
+  .btn {
+    @apply inline-flex items-center justify-center px-4 py-2.5 rounded-xl font-semibold text-sm transition-colors min-h-[44px] disabled:opacity-40 disabled:cursor-not-allowed;
+  }
+  .btn-primary {
+    @apply bg-primary-700 hover:bg-primary-800 text-white;
+  }
+  .btn-secondary {
+    @apply bg-gray-200 hover:bg-gray-300 text-gray-700;
+  }
+  .btn-danger {
+    @apply bg-red-600 hover:bg-red-700 text-white;
+  }
+  .btn-ghost {
+    @apply bg-transparent hover:bg-gray-100 text-gray-600;
+  }
+  .card {
+    @apply bg-white rounded-2xl shadow-sm border border-gray-100;
+  }
+  .input {
+    @apply w-full border border-gray-300 rounded-xl px-4 py-2.5 text-base focus:outline-none focus:ring-2 focus:ring-primary-600 disabled:bg-gray-50;
+  }
+  .label {
+    @apply block text-sm font-medium text-gray-700 mb-1;
+  }
+}