More additions to profiler-edit, for sp3 profiles

[mstange]

This makes it so that you can run profiler-edit with --insert-label-frames browser_labels.toml --only-keep-threads-with-markers-matching='-async,-sync' --merge-non-overlapping-threads-by-name --set-name 'Sp3 5x (with labels, combined main threads)' to turn https://share.firefox.dev/4cXQFED into https://share.firefox.dev/4ezEcsa

The label frames are useful in the JS-only view when applied to profiles from samply; they let us group work like "Paint" and "JS Parsing" (example toml). You can best see them in action in the function list deploy preview: JS-only, ordered by self, with the Self wing showing where the time is spent.

[codecov]

Codecov Report

❌ Patch coverage is 9.09091% with 140 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.37%. Comparing base (2cb282f) to head (e496d7c).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/profile-logic/merge-compare.ts	4.90%	97 Missing ⚠️
src/profile-logic/marker-data.ts	0.00%	28 Missing ⚠️
src/node-tools/profiler-edit.ts	37.50%	15 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6009      +/-   ##
==========================================
- Coverage   83.69%   83.37%   -0.32%     
==========================================
  Files         338      338              
  Lines       35693    35846     +153     
  Branches     9904     9940      +36     
==========================================
+ Hits        29873    29887      +14     
- Misses       5392     5531     +139     
  Partials      428      428              

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