[Discover] chore: Update query editor loading UI

[Maosaic]

Description

Improve query editor loading UX:

1. Spinner in editor footer will show immediately when query start. (time elapsed text will show 3s later)
2. Added a progress bar in query editor
3. Update loading text font

Issues Resolved

Screenshot

Screen.Recording.2025-02-06.at.10.54.49.AM.mp4

Screen.Recording.2025-02-11.at.10.26.18.AM.mp4

Testing the changes

Changelog

• chore: Update query editor loading UI

Check List

• All tests pass
  • yarn test:jest
  • yarn test:jest_integration
• New functionality includes testing.
• New functionality has been documented.
• Update CHANGELOG.md
• Commits are signed per the DCO using --signoff

[codecov]

Codecov Report

Attention: Patch coverage is 25.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 61.71%. Comparing base (8cc5f84) to head (cf089dd).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...query_string/language_service/lib/query_result.tsx	50.00%	0 Missing and 1 partial ⚠️
...c/ui/query_editor/editors/default_editor/index.tsx	0.00%	1 Missing ⚠️
...ins/data/public/ui/query_editor/editors/shared.tsx	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #9344   +/-   ##
=======================================
  Coverage   61.71%   61.71%           
=======================================
  Files        3817     3817           
  Lines       91841    91844    +3     
  Branches    14545    14548    +3     
=======================================
+ Hits        56677    56680    +3     
  Misses      31508    31508           
  Partials     3656     3656           

Flag	Coverage Δ
Linux_1	28.98% <0.00%> (-0.01%)	⬇️
Linux_2	56.46% <ø> (ø)
Linux_3	39.19% <25.00%> (?)
Linux_4	28.90% <0.00%> (-0.01%)	⬇️
Windows_1	29.00% <0.00%> (-0.01%)	⬇️
Windows_2	56.41% <ø> (ø)
Windows_3	39.20% <25.00%> (+<0.01%)	⬆️
Windows_4	28.90% <0.00%> (-0.01%)	⬇️

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