fix: price sync kit components + vat_included type bug

- Fix vat_included comparison: GoMag API returns int 1, not str "1",
  causing all prices to be multiplied by TVA again (double TVA)
- Normalize vat_included to string in gomag_client at parse time
- Price sync now processes kit components individually by looking up
  each component's CODMAT as standalone GoMag product
- Add _insert_component_price for components without existing Oracle price
- resolve_mapped_codmats: ROW_NUMBER dedup for CODMATs with multiple
  NOM_ARTICOLE entries, prefer article with current stock
- pack_import_comenzi: merge_or_insert_articol to merge quantities when
  same article appears from kit + individual on same order

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

api/app/services/sync_service.py

@@ -468,7 +468,8 @@ async def run_sync(id_pol: int = None, id_sectie: int = None, run_id: str = None
                     mapped_codmat_data = {}
                     if mapped_skus_in_orders:
                         mapped_codmat_data = await asyncio.to_thread(
-                            validation_service.resolve_mapped_codmats, mapped_skus_in_orders, conn
+                            validation_service.resolve_mapped_codmats, mapped_skus_in_orders, conn,
+                            id_gestiuni=id_gestiuni
                         )
                         # Build id_map for mapped codmats and validate/ensure their prices
                         mapped_id_map = {}