chore(ci): pin GitHub Actions to immutable commit SHAs

[Copilot]

Description

Pin all GitHub Actions uses: references in .github/workflows/*.yml from floating tags/branch refs to immutable full commit SHAs. This prevents unexpected changes if an action tag is moved, while keeping the original ref as an inline comment (e.g. # v6, # v10.0.2, # release/v1) so maintainers can easily see which version is pinned.

The existing dependabot.yml already configures the github-actions ecosystem with weekly updates, so Dependabot will continue detecting upstream changes and opening PRs to bump the pinned SHAs.

Resolves or fixes issue: #532

AI Tool Disclosure

• My contribution does not include any AI-generated content
• My contribution includes AI-generated content, as disclosed below:
  • AI Tools: GitHub Copilot Coding Agent
  • LLMs and versions: Claude Sonnet 4.5
  • Prompts: Pin all GitHub Actions workflow uses: references to immutable commit SHAs while preserving Dependabot update behavior via inline tag comments.

Affirmation

• My code follows the CONTRIBUTING.md guidelines

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Coverage ∅ diff coverage · +0.00% coverage variation

Metric	Results
Coverage variation	✅ +0.00% coverage variation (-1.00%)
Diff coverage	✅ ∅ diff coverage (80.00%)

View coverage diff in Codacy

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (b3bb790)	1152	1117	96.96%
Head commit (c60e221)	1152 (+0)	1117 (+0)	96.96% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#1043)	0	0	∅ (not applicable)

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

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