Renamed schemas to schema as per naming conventions

app/api/v1/vendor/inventory.py

@@ -9,7 +9,7 @@ from app.api.deps import get_current_user
 from app.core.database import get_db
 from middleware.vendor_context import require_vendor_context
 from app.services.inventory_service import inventory_service
-from models.schemas.inventory import (
+from models.schema.inventory import (
     InventoryCreate,
     InventoryAdjust,
     InventoryUpdate,