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

[GuyAv46]

Combined backport of #1032 and #1031 to 8.4. 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.

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Note

Medium Risk
Changes merge-gating CI (ARM runner platform, Debian/gcc image, and EC2 launch metadata) without touching application code; misconfiguration could block merges or leave runners untagged until workflows are validated.

Overview
CI runner and matrix updates for the 8.4 branch: ARM unit tests no longer provision EC2 start/stop jobs in arm.yml and instead call task-unit-test.yml on GitHub-hosted ubuntu-22.04-arm, dropping AWS secrets inheritance from merge/nightly ARM jobs.

Coverage and benchmark EC2 runners now run a Python step that normalizes github.actor into an owner tag and pass aws-resource-tags (team=ai_and_search, dynamic owner) into machulav/ec2-github-runner at instance start.

Debian CI moves from Bullseye/debian11 to debian13.yml with job trixie and container gcc:14-trixie; merge-queue and nightly workflows swap job names and pr-validation / notify-on-failure dependencies accordingly.

^{Reviewed by Cursor Bugbot for commit 968618c. 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.
✅ Project coverage is 96.97%. Comparing base (ce49e60) to head (968618c).

Additional details and impacted files

@@           Coverage Diff           @@
##              8.4    #1041   +/-   ##
=======================================
  Coverage   96.97%   96.97%           
=======================================
  Files         126      126           
  Lines        7599     7599           
=======================================
  Hits         7369     7369           
  Misses        230      230           

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