Problem

Currently (or when #71630 is merged), we have three block binding sources that create redundancy:

• core/entity - Handles both post-type and taxonomy entities using block attributes
• core/post-data - Handles post entities using block context
• core/term-data - Handles taxonomy entities using block context

The core/entity source duplicates functionality that could be provided by the existing Post and Term data sources, creating unnecessary maintenance overhead and code complexity.

Part of #67520

Goal

Eliminate the core/entity block binding source by enhancing the existing core/post-data and core/term-data sources to support attribute-based data retrieval, making them more flexible and removing the need for a separate entity source.

Solution Outline

1. Enhance Post Data source to support attribute-based data retrieval and add link key support for post-type entities
2. Enhance Term Data source to support attribute-based data retrieval (already has link key for taxonomy entities)
3. Update Navigation Link hook to programmatically choose between Post/Term bindings based on the kind attribute (post-type → core/post-data, taxonomy → core/term-data)
4. Remove Entity source entirely once the enhanced sources are in place

This approach maintains backward compatibility while eliminating redundancy and centralizing entity handling logic in the appropriate domain-specific sources.

Related Work

This issue tracks the requirement to normalize the block binding sources as discussed in PR #71630. The PR implements the initial core/entity binding source, but this issue addresses the follow-up work needed to eliminate redundancy by enhancing the existing Post and Term data sources instead.