fix(BA-5829): break AppConfig <-> AppConfigFragment GQL import cycle

`app_config/types/node.py` imports `AppConfigFragmentGQL` (AppConfig's
`fragments` field), which loads `app_config_fragment/__init__.py`.
That used to eagerly re-export the mutation resolvers, which then
imported back from `app_config.types.bulk_payloads` -> `node` (still
mid-load) -> ImportError.

Three small surgeries break the cycle:

- `app_config_fragment/__init__.py` no longer re-exports its resolver
  symbols; `schema.py` now imports them straight from the resolver
  submodules.
- `app_config/types/__init__.py` no longer re-exports the My-bulk
  payload GQL types, so loading the package no longer drags in
  `bulk_payloads.py` before `node.py` finishes.
- `mutation.py` imports the My-bulk payload types from the
  `bulk_payloads` submodule directly.

`tests/component/user/test_keypair_ops.py` collection (and the
`api-updated` schema-dump step) used to fail because of this cycle.

Author: jopemachine

src/ai/backend/manager/api/gql/app_config/types/__init__.py

@@ -1,7 +1,3 @@
-from .bulk_payloads import (
-    BulkCreateMyAppConfigFragmentsPayloadGQL,
-    BulkUpdateMyAppConfigFragmentsPayloadGQL,
-)
 from .filters import (
     AppConfigFilterGQL,
     AppConfigOrderByGQL,
@@ -14,6 +10,4 @@
     "AppConfigGQL",
     "AppConfigOrderByGQL",
     "AppConfigOrderFieldGQL",
-    "BulkCreateMyAppConfigFragmentsPayloadGQL",
-    "BulkUpdateMyAppConfigFragmentsPayloadGQL",
 ]

src/ai/backend/manager/api/gql/app_config_fragment/__init__.py

@@ -1,38 +1,9 @@
-"""AppConfigFragment GraphQL API package."""
+"""AppConfigFragment GraphQL API package.
 
-from .resolver import (
-    admin_app_config_fragments,
-    admin_bulk_create_app_config_fragments,
-    admin_bulk_purge_app_config_fragments,
-    admin_bulk_update_app_config_fragments,
-    app_config_fragment,
-    bulk_create_my_app_config_fragments,
-    bulk_update_my_app_config_fragments,
-)
-from .types import (
-    AppConfigFragmentFilterGQL,
-    AppConfigFragmentGQL,
-    AppConfigFragmentKeyInputGQL,
-    AppConfigFragmentOrderByGQL,
-    AppConfigFragmentOrderFieldGQL,
-    AppConfigScopeTypeGQL,
-)
-
-__all__ = [
-    # Queries — scope-bound list belongs on DomainV2 / UserV2 child fields
-    "app_config_fragment",
-    "admin_app_config_fragments",
-    # Bulk mutations
-    "admin_bulk_create_app_config_fragments",
-    "admin_bulk_update_app_config_fragments",
-    "admin_bulk_purge_app_config_fragments",
-    "bulk_create_my_app_config_fragments",
-    "bulk_update_my_app_config_fragments",
-    # Types
-    "AppConfigFragmentGQL",
-    "AppConfigScopeTypeGQL",
-    "AppConfigFragmentFilterGQL",
-    "AppConfigFragmentOrderByGQL",
-    "AppConfigFragmentOrderFieldGQL",
-    "AppConfigFragmentKeyInputGQL",
-]
+Resolver and type names are re-exported by ``schema.py`` directly via
+their submodules to keep this package's ``__init__`` import-light: a
+top-level ``from app_config_fragment import ...`` would otherwise drag
+in the mutation resolvers, which back-import from
+``app_config.types.bulk_payloads`` and form an import cycle when
+``AppConfigGQL`` is loading.
+"""

src/ai/backend/manager/api/gql/app_config_fragment/resolver/mutation.py

@@ -5,7 +5,7 @@
 from strawberry import Info
 
 from ai.backend.common.meta.meta import NEXT_RELEASE_VERSION
-from ai.backend.manager.api.gql.app_config.types import (
+from ai.backend.manager.api.gql.app_config.types.bulk_payloads import (
     BulkCreateMyAppConfigFragmentsPayloadGQL,
     BulkUpdateMyAppConfigFragmentsPayloadGQL,
 )

src/ai/backend/manager/api/gql/schema.py

@@ -20,15 +20,17 @@
     my_app_configs,
     public_app_config_fragments,
 )
-from .app_config_fragment import (
-    admin_app_config_fragments,
+from .app_config_fragment.resolver.mutation import (
     admin_bulk_create_app_config_fragments,
     admin_bulk_purge_app_config_fragments,
     admin_bulk_update_app_config_fragments,
-    app_config_fragment,
     bulk_create_my_app_config_fragments,
     bulk_update_my_app_config_fragments,
 )
+from .app_config_fragment.resolver.query import (
+    admin_app_config_fragments,
+    app_config_fragment,
+)
 from .app_config_policy import (
     admin_bulk_create_app_config_policies,
     admin_bulk_purge_app_config_policies,