[8.6] [MOD-18346] Backport CI runner fixes and Debian Trixie

[GuyAv46]

Combined backport of #1032 and #1031 to 8.6. Both fixes are included so CI can validate and merge them together.

• Tag coverage and benchmark EC2 runners at launch with team=ai_and_search and a normalized GitHub actor as owner.
• Run ARM unit tests on GitHub-hosted ubuntu-22.04-arm and remove ARM EC2 provisioning and inherited secrets.
• Replace active Bullseye CI jobs with gcc:14-trixie, rename the Debian installer/workflow, and update workflow dependencies. Preserve release-specific AWS settings and test options.

Fixes MOD-18346.

Validation: parsed workflow YAML, checked local reusable-workflow paths and job dependencies, verified no active Bullseye jobs remain, compiled owner-tag Python, checked EC2 launch tags, and ran shell syntax/whitespace checks. Runtime CI is pending.

---

Note

Medium Risk
Changes CI runner provisioning (ARM off EC2), AWS resource tagging, and the active Debian test image, which can shift pass/fail behavior until pipelines run on the new matrix.

Overview
ARM CI no longer provisions EC2 start/stop jobs in arm.yml; unit tests run on GitHub-hosted ubuntu-22.04-arm via task-unit-test.yml, and merge/nightly flows drop secrets: inherit on the ARM reusable workflow call.

Coverage and benchmark EC2 runners gain a Python step that normalizes github.actor into an owner tag, plus aws-resource-tags (team=ai_and_search, owner=<actor>) on machulav/ec2-github-runner start in coverage.yml and benchmark-runner.yml.

Debian CI moves from Bullseye to Trixie: debian13.yml is renamed to the trixie flow with job trixie and container gcc:14-trixie; merge-queue and nightly workflows call debian13.yml instead of debian11.yml and gate on trixie instead of bullseye.

^{Reviewed by Cursor Bugbot for commit 48eb022. Bugbot is set up for automated code reviews on this repo. Configure here.}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (8.6@be0aeae). Learn more about missing BASE report.

Additional details and impacted files

@@          Coverage Diff           @@
##             8.6    #1042   +/-   ##
======================================
  Coverage       ?   96.91%           
======================================
  Files          ?      129           
  Lines          ?     7710           
  Branches       ?        0           
======================================
  Hits           ?     7472           
  Misses         ?      238           
  Partials       ?        0           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.