Factor out tree identifier compression and healing utils

[CraigMacomber]

Description

Factor out tree identifier compression and healing utils.

This will make it practical to remove the originator id (which is incorrect) that is passed down into some of the codecs: they can use the new helper functions to do the conversions they need without it, and will produce better errors if they do hit the bug.

Then updated formats/versions of the codecs can be added which require the originator id (and don't need these workarounds) and the distinction between these two cases will be clean.

Reviewer Guidance

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[github-actions]

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Based on the diff (638 lines, 13 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

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[github-actions]

🔗 No broken links found! ✅

Your attention to detail is admirable.

linkcheck output

> fluid-framework-docs-site@0.0.0 ci:check-links /home/runner/work/FluidFramework/FluidFramework/docs
> start-server-and-test "npm run serve -- --no-open" 3000 check-links

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-docs-site@0.0.0 serve
> docusaurus serve --no-open

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

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

Crawling...

Stats:
  288859 links
    1925 destination URLs
    2175 URLs ignored
       0 warnings
       0 errors