feat(sync): handle cancelled GoMag orders (status Anulata / statusId 7)

- Add web_status column to orders table (generic name for platform status)
- Filter cancelled orders during sync, record as CANCELLED in SQLite
- Soft-delete previously-imported cancelled orders in Oracle (if not invoiced)
- Add CANCELLED filter pill + badge in dashboard UI
- New soft_delete_order_in_roa() and mark_order_cancelled() functions

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/app/database.py

@@ -109,7 +109,8 @@ CREATE TABLE IF NOT EXISTS orders (
     invoice_checked_at    TEXT,
     order_total           REAL,
     delivery_cost         REAL,
-    discount_total        REAL
+    discount_total        REAL,
+    web_status          TEXT
 );
 CREATE INDEX IF NOT EXISTS idx_orders_status ON orders(status);
 CREATE INDEX IF NOT EXISTS idx_orders_date ON orders(order_date);
@@ -316,6 +317,7 @@ def init_sqlite():
             ("order_total", "REAL"),
             ("delivery_cost", "REAL"),
             ("discount_total", "REAL"),
+            ("web_status", "TEXT"),
         ]:
             if col not in order_cols:
                 conn.execute(f"ALTER TABLE orders ADD COLUMN {col} {typedef}")