Expand CI test matrices and versions

[priethor]

What

Expand PHP and Node.js version matrices in CI workflows while optimizing PR time by testing only essential versions on pull requests.

Why

Current workflows only test limited versions, missing potential compatibility issues, but the full version matrix on every PR is slow and resource-intensive.

How

• e2e.yml: Added Node 20, 22, 24 matrix; PRs test Node 22 only; trunk tests all
• phpunit.yml: Added PHP 7.4–8.4 matrix; PRs test 7.4 and 8.4 only; trunk tests all
• Added concurrency control to cancel outdated workflow runs
• Added workflow_dispatch for manual triggering
• Added explicit permissions restrictions

Testing Instructions

Check the CI jobs in this PR

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 7.48%. Comparing base (65d8085) to head (417ff67).
⚠️ Report is 1 commits behind head on trunk.

Additional details and impacted files

@@            Coverage Diff             @@
##             trunk    #254      +/-   ##
==========================================
+ Coverage     3.69%   7.48%   +3.78%     
  Complexity    4282    4282              
==========================================
  Files          197     265      +68     
  Lines        26154   33069    +6915     
==========================================
+ Hits           967    2474    +1507     
- Misses       25187   30595    +5408     

Flag	Coverage Δ
e2e	21.79% <ø> (?)
phpunit	3.69% <ø> (ø)

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[github-actions]

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