chore(*): Hide overridden members in inherited type.

[MayaKirova]

Related to this

Additional information (check all that apply):

• Bug fix
• New functionality
• Documentation
• Demos
• CI/CD

Checklist:

• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code (test guidelines)
• This PR includes API docs for newly added methods/properties (api docs guidelines)
• This PR includes feature/README.MD updates for the feature docs
• This PR includes general feature table updates in the root README.MD
• This PR includes CHANGELOG.MD updates for newly added functionality
• This PR contains breaking changes
• This PR includes ng update migrations for the breaking changes (migrations guidelines)
• This PR includes behavioral changes and the feature specification has been updated with them

[Copilot]

Pull request overview

This PR addresses API documentation/surface duplication in the Hierarchical Grid by hiding an overridden inherited member (advancedFilteringExpressionsTree) on IgxHierarchicalGridComponent, while preserving its runtime behavior (including the schema initialization on set).

Changes:

• Marked the overridden advancedFilteringExpressionsTree getter and setter as @hidden @internal to avoid exposing duplicate/inherited API members in generated docs/type surfaces.