[migration] Make CI status and dashboard repository-portable #4985

Parent: #4960
Depends on: portable repository identity foundation

Extract CI-status and active dashboard repository identity from #4964.

Scope

• Build the CI workflow registry from one current repository identity and the docs submodule identity.
• Preserve permanent Azure pipeline IDs/names such as definition 345 and mono-SkiaSharp unless infrastructure deliberately renames them.
• Make documentation/registry validation non-vacuous under both mono and simulated dotnet contexts.
• Render current AI/dashboard source links from resolved identities without rewriting historical data.

Exclusions

• No Azure definition rename/rebind, release notes, packages/site deployment, gh-aw workflow gates, or Backport.

Completion

• CI status tracks the same workflows before/after transfer and tests every expected row in both contexts.