Rename TModel TypeVar to _TModel to fix broken doc links

[Copilot]

DocFx treats module-level TypeVar instances as public documented types and generates <xref:...TModel> cross-reference links that resolve to nothing, producing broken links in the AgentNotificationActivity.as_model documentation.

Change

Rename the module-scope TypeVar from TModel to _TModel in agent_notification_activity.py. The underscore prefix marks it as private; doc generators skip cross-reference link generation for private symbols and render the type as plain text instead.

# before
TModel = TypeVar("TModel")

def as_model(self, model: Type[TModel]) -> Optional[TModel]: ...

# after
_TModel = TypeVar("_TModel")

def as_model(self, model: Type[_TModel]) -> Optional[_TModel]: ...

This also aligns with standard Python convention: TypeVars not part of a public generic API should always be underscore-prefixed.

[github-actions]

⚠️ Deprecation Warning: The deny-licenses option is deprecated for possible removal in the next major release. For more information, see issue 997.

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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[Copilot]

Pull request overview

This PR addresses broken DocFx cross-reference links by making a module-level TypeVar private in AgentNotificationActivity, preventing it from being treated as a public documented symbol.

Changes:

• Renamed the module-scope TypeVar from TModel to _TModel.
• Updated AgentNotificationActivity.as_model type annotations to use _TModel.

[Copilot]

as_model calls model.model_validate(...), but the annotation model: Type[_TModel] doesn’t guarantee that the passed type has a model_validate classmethod. Consider bounding _TModel to pydantic.BaseModel (or using type[BaseModel] directly) so static type checkers can validate correct usage.

[JimDaly]

After consulting with the learn platform team, closing this since it may not fix the problem.