ci: migrate build and CodeQL to GitHub-hosted runners

[MarkBedrock]

CI Migration: Move Bedrock CI & CodeQL to GitHub-Hosted Runners

Summary

This PR modernizes Bedrock’s continuous integration setup by migrating all required CI jobs from the self-hosted dev-01 runner to GitHub-hosted runners (ubuntu-latest).
Self-hosted runners remain available for optional heavy/soak workflows, but no longer gate merges or block PRs when offline.

This is part of the Side Quest: CI Modernization & Hygiene, and aligns Bedrock CI with Phoenix’s new GitHub-hosted CI architecture.

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Key Changes

1. Migrate CI / build to GitHub-hosted runner

File changed: .github/workflows/ci.yml
• Replaced:

runs-on: [self-hosted, linux, x64, dev01, fastpath]

with:

runs-on: ubuntu-latest

•	Added standard Ubuntu dependency setup via apt-get
•	Removed dev-01 specific logic (ccache setup, dnf, runner labels, etc.)
•	Build + test jobs now run consistently on GitHub infrastructure

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2. Migrate CodeQL to GitHub-hosted runners

File changed: .github/workflows/codeql.yml
• Replaced:

runs-on: [self-hosted, linux, x64, dev01, fastpath]

with:

runs-on: ubuntu-latest

•	Added pull_request trigger (previously missing)
•	Left all CodeQL init/analyze steps intact
•	CodeQL now runs without depending on dev-01 availability

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3. Fix auto-merge.yml required check names

File changed: .github/workflows/auto-merge.yml

Updated check names so dependabot auto-merge recognizes the actual status checks emitted by GitHub:
• "CI / build" instead of "CI"
• "CodeQL Analysis" instead of "CodeQL"

This resolves silent auto-merge failures caused by mismatched check names.

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Why This Change Is Needed

Before this PR:
• CI jobs were locked to the self-hosted dev-01 runner
• When dev-01 was offline, CI stalled indefinitely
• PR Guard showed “Expected — Waiting for status…” deadlocks
• CodeQL never ran on PRs
• auto-merge workflows had stale check name expectations

After this PR:
• All required checks run on GitHub infrastructure
• Bedrock CI is now:
• Reliable
• Scalable
• Independent of local hardware
• Consistent across contributors

Self-hosted runners remain available for non-required soak/perf tests.

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Validation

✔ Builds on GitHub-hosted ubuntu-latest
• Full build + test run completes successfully
• No dev-01-specific paths remain
• No unexpected toolchain differences

✔ CodeQL runs successfully on PRs
• Correct triggers
• No dependency errors
• Fully GitHub-infra based

✔ auto-merge workflows now match actual check names

✔ No changes to core Bedrock code or behavior

This PR touches only workflow files.

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Files Changed (High-level)

.github/workflows/ci.yml
.github/workflows/codeql.yml
.github/workflows/auto-merge.yml

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Next Steps (Post-Merge)

After merging this PR:
1. Update branch protection rules (manual GitHub UI step):
• Required:
• CI / build
• CodeQL Analysis
• validate (if applicable)
• Remove any self-hosted required checks
2. Optional in future PRs:
• Migrate soak/heartbeat jobs off self-hosted runners if desired
• Add macOS or Windows CI as separate jobs
• Add cache rehydration steps for faster builds

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Confidence

This PR implements exactly the plan outlined in:
• BEDROCK_CI_HYGIENE_AUDIT.md
• CI_MIGRATION_PLAN.md

All edits were performed on the feature/ci-migration branch and validated locally before opening this PR.

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