ENG-12577: Align docs breadcrumbs with public canonical URLs

[carlosabadia]

Docs breadcrumb JSON-LD currently derives its origin from the deployment config, producing localhost URLs while canonical tags point to the public site. Reuse the existing DOCS_PROD_BASE (https://reflex.dev/docs) for breadcrumbs, matching the canonical URLs without changing deploy_url, runtime configuration, or routing.

Update the shared mobile menu's Auth link to /docs/enterprise/auth/overview/. Extend the exported SEO test to verify breadcrumb positions, labels, final canonical destination, and membership in the public sitemap. Existing Cloudflare redirects remain unchanged.

Validation:

• Regression tests reproduced the bad breadcrumb origins and legacy Auth link before the fixes.
• Docs unit suite: 545 passed, 1 skipped, 6 build-dependent xfails before export; browser suites excluded.
• Full frontend export succeeds. All 421 published pages pass the canonical, social, Markdown, internal-link and breadcrumb checks; all five post-build SEO checks pass.
• All 421 docs routes, negotiated Markdown responses and explicit Markdown files pass through the existing Caddy config.
• Full repository pre-commit passes.

After merge, rebuild the docs image from the merged Reflex source revision and verify the deployed metadata. No image build or deployment has been triggered by this PR.

[linear-code]

ENG-12577

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge with no actionable correctness, security, or repository-rule issues identified.

Summary

This PR aligns documentation breadcrumb JSON-LD with the public canonical docs origin and updates the shared mobile Auth navigation destination.

• Uses DOCS_PROD_BASE for canonical breadcrumb entries regardless of deployment configuration.
• Extends exported-site SEO validation to check breadcrumb structure, ordering, canonical destinations, and sitemap membership.
• Points the mobile Auth entry directly to the current enterprise authentication overview and adds regression coverage.
• Adds the required shared-package bugfix news fragment.

_{Reviews (1) · Last reviewed commit: "Remove docs breadcrumb news fragment"}

[codspeed]

Merging this PR will not alter performance

✅ 67 untouched benchmarks
⏩ 17 skipped benchmarks¹

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Footnotes

1. 17 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[cubic-dev-ai]

No issues found across 6 files

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