ci: update ci build matrix

[inkydragon]

Test with:

• [ubuntu-latest, windows-latest, macos-15-intel] x [x64] x ['lts', '1']
• macos-latest x [aarch64] x ['lts', '1']
• ubuntu-latest x [x86] x ['1']
• (tier 2) ubuntu-24.04-arm x [aarch64] x ['1']

replace #313, fix #315

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.42%. Comparing base (cadbbc1) to head (2ad6377).
⚠️ Report is 15 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #316      +/-   ##
==========================================
+ Coverage   92.92%   96.42%   +3.50%     
==========================================
  Files           7        7              
  Lines         735      784      +49     
==========================================
+ Hits          683      756      +73     
+ Misses         52       28      -24     

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[Copilot]

Pull request overview

This PR consolidates ARM architecture testing by removing the separate UnitTestArm.yml workflow and integrating ARM testing into the main UnitTest.yml workflow. The changes modernize the CI configuration by adding concurrency controls, updating Julia version specifiers, and attempting to use native ARM runners instead of emulation.

Key Changes:

• Removes separate ARM workflow that used Docker-based emulation via uraimo/run-on-arch-action
• Adds concurrency configuration to cancel redundant PR builds
• Updates Julia version testing from '1.6' to 'lts' and attempts to add native ARM runner support

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 5 comments.

File	Description
.github/workflows/UnitTestArm.yml	Deleted - separate ARM workflow using Docker emulation removed
.github/workflows/UnitTest.yml	Updated to consolidate testing, add concurrency controls, attempt ARM runner integration, and modernize Julia version specs

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[Copilot]

The runner name 'ubuntu-24.04-arm' does not appear to be a standard GitHub-hosted runner. GitHub does not currently provide ARM-based Ubuntu runners as standard hosted runners. If ARM testing on Ubuntu is required, you would typically need to use self-hosted runners or alternative solutions. Consider using 'ubuntu-latest' with emulation (via setup-julia's arch parameter), or set up self-hosted ARM runners. If this is intended to be a self-hosted runner, ensure it's properly configured in your repository settings.

Suggested change

	- os: ubuntu-24.04-arm
	julia-version: 'lts'
	julia-arch: aarch64
	- os: ubuntu-24.04-arm
	- os: ubuntu-latest
	julia-version: 'lts'
	julia-arch: aarch64
	- os: ubuntu-latest

[ViralBShah]

@copilot resolve the merge conflicts in this pull request

[Copilot]

@copilot resolve the merge conflicts in this pull request

Merge conflicts resolved in commit 145b924. The two conflicts were:

1. .github/workflows/UnitTest.yml — kept our branch's steps (cache@v2, julia-buildpkg@v1, julia-runtest@v1)
2. .github/workflows/UnitTestArm.yml — kept the deletion (ARM testing is consolidated into the main workflow)