feat(sqlite): refactor orders schema + dashboard period filter

Replace import_orders (insert-per-run) with orders table (one row per
order, upsert on conflict). Eliminates dedup CTE on every dashboard
query and prevents unbounded row growth at 4-500 orders/sync.

Key changes:
- orders table: PK order_number, upsert via ON CONFLICT DO UPDATE;
  COALESCE preserves id_comanda once set; times_skipped auto-increments
- sync_run_orders: lightweight junction (sync_run_id, order_number)
  replaces sync_run_id column on orders
- order_items: PK changed to (order_number, sku), INSERT OR IGNORE
- Auto-migration in init_sqlite(): import_orders → orders on first boot,
  old table renamed to import_orders_bak
- /api/dashboard/orders: period_days param (3/7/30/0=all, default 7)
- Dashboard: period selector buttons in orders card header
- start.sh: stop existing process on port 5003 before restart;
  remove --reload (broken on WSL2 /mnt/e/)
- Add invoice_service, E2E Playwright tests, Oracle package updates

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

api/app/routers/validation.py

@@ -88,9 +88,9 @@ async def scan_and_validate():
 async def get_missing_skus(
     page: int = Query(1, ge=1),
     per_page: int = Query(20, ge=1, le=100),
-    resolved: int = Query(0, ge=0, le=1)
+    resolved: int = Query(0, ge=-1, le=1)
 ):
-    """Get paginated missing SKUs."""
+    """Get paginated missing SKUs. resolved=-1 means show all (R10)."""
     result = await sqlite_service.get_missing_skus_paginated(page, per_page, resolved)
     # Backward compat: also include 'unresolved' count
     db = await get_sqlite()
@@ -106,7 +106,7 @@ async def get_missing_skus(
 
 @router.get("/missing-skus-csv")
 async def export_missing_skus_csv():
-    """Export missing SKUs as CSV."""
+    """Export missing SKUs as CSV compatible with mapping import (R8)."""
     db = await get_sqlite()
     try:
         cursor = await db.execute("""
@@ -120,9 +120,9 @@ async def export_missing_skus_csv():
 
     output = io.StringIO()
     writer = csv.writer(output)
-    writer.writerow(["sku", "product_name", "first_seen"])
+    writer.writerow(["sku", "codmat", "cantitate_roa", "procent_pret", "product_name"])
     for row in rows:
-        writer.writerow([row["sku"], row["product_name"], row["first_seen"]])
+        writer.writerow([row["sku"], "", "", "", row["product_name"] or ""])
 
     return StreamingResponse(
         io.BytesIO(output.getvalue().encode("utf-8-sig")),