Clarify transcripts route metadata as page-only (not console tab UI_META)

[Copilot]

This PR addresses the linked review-thread feedback to implement outstanding comment fixes with minimal scope. Specifically, it resolves the transcripts metadata comment by making the module intent explicit and aligned with current /api/v1/ui/structure collection behavior.

• Problem alignment

  • Updated the transcripts route metadata symbol to avoid implying it is part of console tab aggregation.

• Code change

  • In python/routes/transcripts.py, renamed:
    • UI_META → PAGE_META
  • Added an inline note clarifying this metadata is for the standalone /transcripts top-nav page and is not consumed by collect_ui_meta().

• Net effect

  • Removes ambiguity that triggered the review comment without expanding scope into collector behavior changes.

# Standalone top-nav page metadata (not a console tab; not consumed by collect_ui_meta).
PAGE_META = {"label": "Transcripts", "module": "transcripts", "order": 25, "path": "/transcripts"}