chore: clean up build warnings

[Ethan-Arrowood]

What and why

Two unrelated warnings have been firing during every docs build since Phase 1 (#497) landed. Both are now fixed. A third "Excluded N routes by current config" warning remains but is just accurate accounting of intentional exclusions — not noise we need to silence.

Fix 1: /reference route processing failure

src/pages/reference/index.tsx is a client-side React redirect component that returns null — its rendered HTML is an empty Docusaurus shell with no extractable content. The llms-txt plugin was attempting to process it and emitting:

[WARNING] [docusaurus-plugin-llms-txt] Route Error: Failed to process route "/reference":
Failed to convert HTML to Markdown: HTML to Markdown conversion resulted in empty content
for "reference.html". This usually means your contentSelectors didn't match any elements...

Fix: add /reference to the plugin's excludeRoutes config. This is not a content page; it's a routing redirect that should never be considered for the flat-markdown export.

Fix 2: Broken anchor in resource-api.md

reference/resources/resource-api.md (line 799) linked to ../components/javascript-environment.md#transaction, but the heading ### `transaction(fn)` in that target file gets the auto-generated anchor transactionfn (parens stripped, dash dropped). The link wanted the semantic name transaction, not the auto-id.

The Docusaurus build was complaining:

[WARNING] Docusaurus found broken anchors!
- Broken anchor on source page path = /reference/v5/resources/resource-api:
   -> linking to /reference/v5/components/javascript-environment#transaction

Fix: add an explicit {#transaction} anchor to the heading in javascript-environment.md. This gives the link a stable, human-meaningful target that survives heading-text changes and matches the original author intent. Docusaurus 3.x supports the {#id} syntax natively.

Verification

• Rebuild produces the same 371 documents across all four docs plugin instances (learn: 10, reference: 137, fabric: 10, release-notes: 211)
• Both targeted warnings are gone
• grep 'id="[^"]*transaction[^"]*"' build/reference/v5/components/javascript-environment.html now returns id="transaction" directly on the heading

Remaining warning (intentional, not fixed)

[WARNING] [docusaurus-plugin-llms-txt] WARNING: Excluded 2 routes by current config

This is the plugin reporting that two routes were filtered:

• The home page / — a content-pages route, excluded by default via includePages: false
• /reference — our new explicit exclusion

Both are intentional. Keeping this warning visible is useful signal — it lets us notice if we accidentally exclude more routes in the future.

🤖 Generated with Claude Code

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