Change that fixes issue 92

[isaac-rtc]

Problem

Repository tags generated from GitHub topics were overwriting the existing tags field in code.json.

This caused any tags that had been manually added to code.json (but did not exist as GitHub repository topics) to be removed the next time the metadata generator ran. As a result, custom tags such as featured would be lost in future generated PRs.

Solution

Added a mergeTags helper that combines the detected GitHub repository topics with the existing code.json tags while removing duplicates.

Instead of replacing the existing tags when repository topics are present, the metadata generator now merges both sources, preserving manually added tags while still including the repository topics.

Tests

Added unit tests covering the new merge behavior:

• Preserves existing tags that are not repository topics

  • Verifies that tags present only in code.json are retained after metadata generation.

• Does not duplicate tags that already exist as repository topics

  • Verifies that tags appearing in both GitHub repository topics and code.json are included only once.

• Uses repository topics when no existing code.json is present

  • Verifies that repositories without an existing code.json continue to use the detected GitHub repository topics as before.

  Closes Metadata: Preserve tags that are not repo topics by adding as repo topics #92

[sachin-panayil]

great work! exactly what the ticket asked for an in a efficient way