feat(ci): optimize integration tests by reusing test-runner images (#24052)

Add GitHub Container Registry (GHCR) image reuse for integration test runners:
- Cache test-runner images in GHCR tagged by Rust version
- Reuse existing images when available to skip rebuild time
- Add cleanup workflow to remove untagged GHCR images
- Update ci-integration-review.yml to use cached images
- Update integration.yml workflow to push images to GHCR

This reduces CI time by avoiding redundant test-runner image builds
when the Rust version hasn't changed.

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Co-authored-by: Claude <noreply@anthropic.com>