feat(125): invoice_requested import fix + drop legacy is_invoice column

- shopPRO: ShopproOrderMapper jako jedyne zrodlo heurystyki detekcji faktury;
  mapOrderAggregate() zwraca top-level invoice_detected (transient).
- ShopproOrdersSyncService: usunieta wlasna shouldRequestInvoice(); propagacja
  aggregate['invoice_detected'] do setInvoiceRequested() tylko przy created=true.
- Allegro: nowa shouldRequestInvoice(payload) z 4 wzorcami (invoice.required,
  naturalPerson=false, address.taxId, companyName/address.company.name).
  Wczesniej tylko invoice.required -> analogiczna luka jak shopPRO.
- Migracja 20260513_000113: idempotentny backfill (UPDATE invoice_requested=1
  WHERE is_invoice=1 AND invoice_requested=0) + DROP COLUMN orders.is_invoice.
  Guard przez information_schema.COLUMNS + PREPARE/EXECUTE z ALTER TABLE COMMENT
  no-op fallbackiem (portable MySQL/MariaDB).
- Cleanup is_invoice z OrderImportRepository (INSERT cols/values/params,
  docstring Phase 112) i OrdersRepository (paginate SELECT, transformOrderRow
  hydrate). AllegroOrderImportService mapping w mapCheckoutFormPayload tez
  usuniety (wymuszone konsekwencja DROP COLUMN).
- Bugfix #1089: zamowienie shopPRO z firm_nip (bez wants_invoice/invoice.required)
  ustawia teraz invoice_requested=1 -> UI w zakladce Platnosci zaznacza checkbox,
  przycisk "Wystaw fakture" widoczny.

Pending operator: php bin/migrate.php (XAMPP MySQL online) -> backfill 7 zamowien.
Smoke test: re-import shopPRO + nowe Allegro z NIP.

database/migrations/20260513_000113_drop_orders_is_invoice_and_backfill_invoice_requested.sql

@@ -0,0 +1,27 @@
+-- Phase 125-01: backfill invoice_requested z is_invoice + DROP COLUMN is_invoice
+-- Idempotentna: guard przez information_schema.COLUMNS; no-op po pierwszym uruchomieniu.
+-- Pattern z Key Decision 2026-05-10: migracje no-op zawsze jako DDL (ALTER TABLE COMMENT),
+-- nigdy SELECT 1; (PDO unbuffered + result set -> SQLSTATE 2014).
+
+SET @col_exists := (
+  SELECT COUNT(*) FROM information_schema.COLUMNS
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'orders'
+    AND COLUMN_NAME = 'is_invoice'
+);
+
+SET @sql_backfill := IF(@col_exists > 0,
+  'UPDATE orders SET invoice_requested = 1 WHERE is_invoice = 1 AND invoice_requested = 0',
+  'ALTER TABLE orders COMMENT = ''phase-125 backfill no-op'''
+);
+PREPARE stmt_backfill FROM @sql_backfill;
+EXECUTE stmt_backfill;
+DEALLOCATE PREPARE stmt_backfill;
+
+SET @sql_drop := IF(@col_exists > 0,
+  'ALTER TABLE orders DROP COLUMN is_invoice',
+  'ALTER TABLE orders COMMENT = ''phase-125 drop no-op'''
+);
+PREPARE stmt_drop FROM @sql_drop;
+EXECUTE stmt_drop;
+DEALLOCATE PREPARE stmt_drop;