Prepare Python SDK 0.147.0 stable release (#39155)

## What changed

- Pin `openai-codex` to the `0.147.0` CLI runtime and regenerate its protocol models and lockfile.
- Allow stable Python SDK release tags and require their versions to match the pinned runtime.
- Expose the regenerated API additions, including thread sections, environment connection notifications, audio inputs, and the `section_id` thread-list filter.

## Testing

- Update release staging, generated-contract, notification, and public-signature coverage for the new runtime.

GitOrigin-RevId: 8b99ef6781e01c34d9d697c8c44247fb4e4fe3ab

sdk/python/src/openai_codex/generated/notification_registry.py

@@ -15,6 +15,7 @@ from .v2_all import CommandExecutionOutputDeltaNotification
 from .v2_all import ConfigWarningNotification
 from .v2_all import ContextCompactedNotification
 from .v2_all import DeprecationNoticeNotification
+from .v2_all import EnvironmentConnectionNotification
 from .v2_all import ErrorNotification
 from .v2_all import ExternalAgentConfigImportCompletedNotification
 from .v2_all import ExternalAgentConfigImportProgressNotification
@@ -119,6 +120,8 @@ NOTIFICATION_MODELS: dict[str, type[BaseModel]] = {
     "thread/closed": ThreadClosedNotification,
     "thread/compacted": ContextCompactedNotification,
     "thread/deleted": ThreadDeletedNotification,
+    "thread/environment/connected": EnvironmentConnectionNotification,
+    "thread/environment/disconnected": EnvironmentConnectionNotification,
     "thread/goal/cleared": ThreadGoalClearedNotification,
     "thread/goal/updated": ThreadGoalUpdatedNotification,
     "thread/name/updated": ThreadNameUpdatedNotification,