promote FluidIterable, FluidIterableIterator, FluidReadonlyMap, FluidMap to public

[jenn-le]

Description

Promotes FluidIterable, FluidIterableIterator, FluidReadonlyMap, and FluidMap from @beta to @public in @fluidframework/core-interfaces.

These sealed interfaces provide TypeScript-version-independent alternatives to the built-in Iterable, IterableIterator, ReadonlyMap, and Map types. They are now stable enough to be referenced in @public API surfaces, a follow-up PR will create a breaking change to migrate our types off of the built-in interfaces in the 3.0 release.

This is a non-breaking, additive change — no existing consumer code is affected.

Reviewer Guidance

The review process is outlined on this wiki page.

• This is purely a release tag promotion (@beta → @public). No functional changes.

[github-actions]

Hi! Thank you for opening this PR. Want me to review it?

Based on the diff (265 lines, 12 files), I've queued these reviewers:

• Correctness — logic errors, race conditions, lifecycle issues
• Security — vulnerabilities, secret exposure, injection
• API Compatibility — breaking changes, release tags, type design
• Performance — algorithmic regressions, memory leaks
• Testing — coverage gaps, hollow tests

How this works

• Adjust the reviewer set by ticking/unticking boxes above. Reviewer toggles alone don't trigger anything.

• Tick Start review below to dispatch the review fleet.

• After review finishes, tick Start review again to request another run — it auto-resets after each dispatch.

• This comment updates as new commits land; your reviewer selections are preserved.

• Start review

[Copilot]

Copilot reviewed 12 out of 12 changed files in this pull request and generated no comments.

[github-actions]

🔗 No broken links found! ✅

Your attention to detail is admirable.

linkcheck output

1: starting server using command "npm run serve -- --no-open"
and when url "[ 'http://127.0.0.1:3000' ]" is responding with HTTP status code 200
running tests using command "npm run check-links"


> fluid-framework-website@0.0.0 serve
> docusaurus serve --no-open

[SUCCESS] Serving "build" directory at: http://localhost:3000/

> fluid-framework-website@0.0.0 check-links
> linkcheck http://localhost:3000 --skip-file skipped-urls.txt

Crawling...

Stats:
  306030 links
    1955 destination URLs
    2209 URLs ignored
       0 warnings
       0 errors

[github-actions]

Bundle size comparison

Base commit: 4a1738e115bfbf0fe60fcc09d4685d56d2a2a918
Head commit: 0105d59ff1a77c67fdebe973a2bb0f24f7e96a1d

⚠️ Comparison unavailable.

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