Initial kitchen scaffold — Phase 1 kitchen port (build-verified 2026-07-11)

FastAPI backend (Python 3.11, MSSQL ODBC for SambaPOS, Azure DI OCR),
kitchen_db on central PG. React/TS/Vite frontend with navy sidebar layout.

Backend: auth.py (APP_SLUG=kitchen, SimpleNamespace — archive routes use
.kitchen_id/.is_admin without modification), main.py (51 migrations, scheduler,
internal router for KDS bookings feed), api/internal.py, full archive API
(31 routers: invoices, recipes, menus, sambapos, resos, newbook, disputes,
purchase_orders, etc.), models, migrations, OCR pipeline.
kitchen_id pinned to 1 (B1 — single hotel).

Frontend: AuthGate (app=kitchen, token shim for archive compat — B5b pending),
Layout (navy sidebar, 6 sections, Lucide icons, teal --app-primary),
App.tsx (Outlet pattern, UploadApp outside Layout), index.css (full :root block).
strict: false — archive components have type issues; build clean.

Note: 45 archive components call fetch('/api/...') without /kitchen/ prefix
(B5b). Runtime 404s; deferred until after initial testing.

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

backend/migrations/add_changelog_invoice_link.py

@@ -0,0 +1,24 @@
+"""
+Migration: Add source_invoice_id to recipe_change_log
+Links price change entries back to the triggering invoice for traceability.
+"""
+import asyncio
+from sqlalchemy import text
+from database import engine
+
+
+async def migrate():
+    async with engine.begin() as conn:
+        await conn.execute(text(
+            "ALTER TABLE recipe_change_log ADD COLUMN IF NOT EXISTS "
+            "source_invoice_id INTEGER REFERENCES invoices(id) ON DELETE SET NULL"
+        ))
+        await conn.execute(text(
+            "CREATE INDEX IF NOT EXISTS idx_recipe_change_log_invoice "
+            "ON recipe_change_log(source_invoice_id)"
+        ))
+    print("+ Added source_invoice_id to recipe_change_log")
+
+
+if __name__ == "__main__":
+    asyncio.run(migrate())