ci: auto-apply clang-tidy fixes on push/schedule via persistent autofix PR

[Copilot]

Briefly, what does this PR introduce? Please link to any relevant presentations or discussions.

On push and schedule, clang-tidy previously produced diagnostics/artifacts but did not apply fixes or maintain an autofix PR lifecycle. This change makes clang-tidy apply fixes and route them through a stable branch/PR that is updated on subsequent runs.

• Clang-tidy execution change
  • Enables in-place autofix for non-PR runs by adding -fix -format to the all-files invocation.
• Autofix PR lifecycle
  • Adds a create-pull-request step for push/schedule.
  • Uses a stable branch name: clang-tidy-${{ github.ref_name }}.
  • Targets the source branch (base: ${{ github.ref_name }}), so existing PRs are updated; missing ones are created.
• PR metadata
  • Uses dedicated bot token, deterministic commit message, and generated PR title/body tied to the workflow run.

- name: Run clang-tidy on all files
  if: ${{ github.event_name == 'push' || github.event_name == 'schedule' }}
  run: run-clang-tidy -p build -fix -format -export-fixes clang_tidy_fixes.yaml -extra-arg='-std=c++20'

- name: Create/Update clang-tidy Pull Request
  if: ${{ github.event_name == 'push' || github.event_name == 'schedule' }}
  with:
    branch: clang-tidy-${{ github.ref_name }}
    base: ${{ github.ref_name }}

What is the urgency of this PR?

• High (please describe reason below)
• Medium
• Low

What kind of change does this PR introduce?

• Bug fix (issue #__)
• New feature (issue #__)
• Optimization (issue #__)
• Updated parameters, constants (issue #__)
• Updated documentation
• other: __

Please check if any of the following apply

• This PR requires changes to geometry (epic PR: __)
• This PR requires changes to EDM4eic (EDM PR: __)
• This PR introduces breaking changes. Please describe changes users need to make below.
• This PR changes default behavior. Please describe changes below.
• AI was used in preparing this PR. Please describe usage below.

AI was used to draft and apply the workflow update and prepare this PR summary.

[Copilot]

Pull request overview

This PR updates the linux-eic-shell GitHub Actions workflow so that, on push and schedule, clang-tidy runs with in-place autofix enabled and the resulting changes are routed through a persistent “autofix” pull request branch that is updated on subsequent runs.

Changes:

• Run clang-tidy on all files with -fix -format for push/schedule events.
• Add a peter-evans/create-pull-request step to create/update a stable clang-tidy-${{ github.ref_name }} PR targeting the source branch.

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[github-actions]

Capybara summary for PR 2813

• rec_dis_10x100_minQ2=0_craterlake_10x100_MT (Δ: 397)
• rec_dis_10x100_minQ2=1000_craterlake_tracking_2DStrip (Δ: 0)
• rec_dis_10x100_minQ2=1000_craterlake_tracking_only (Δ: 0)
• rec_dis_10x130_minQ2=1_craterlake_10x130 (Δ: 0)
• rec_dis_10x250_minQ2=1_craterlake_10x250 (Δ: 0)
• rec_dis_18x275_minQ2=0_craterlake_18x275 (Δ: 0)
• rec_dis_18x275_minQ2=0_craterlake_18x275_MT (Δ: 322)
• rec_dis_18x275_minQ2=0_craterlake_18x275_ST_MT (Δ: 316)
• rec_dis_18x275_minQ2=1000_craterlake_18x275 (Δ: 0)
• rec_dis_18x275_minQ2=1000_craterlake_18x275_MT (Δ: 922)
• rec_dis_18x275_minQ2=1000_craterlake_18x275_ST_MT (Δ: 700)
• rec_dis_5x41_minQ2=0_craterlake_5x41 (Δ: 0)
• rec_e_1GeV_20GeV_craterlake (Δ: 0)
• rec_pi_1GeV_20GeV_craterlake (Δ: 2)
• two_stage_raw_e_1GeV_20GeV_craterlake (Δ: 0)
• two_stage_rec_e_1GeV_20GeV_craterlake (Δ: 0)

Last updated 2026-08-02T12:18-04:00 535d768

[wdconinc]

Works per #2820. Not saying that's what we should merge, but it gives the set of suggestions we think we should enforce in PRs, so we should adjust clang-tidy config if not correct.