ci: move workflow jobs to dind-sm-standard-4 and sm-standard-2 runners

[majinghe]

Type of Change

• New Feature
• Bug Fix
• Documentation
• Performance Improvement
• Test/CI
• Refactor
• Other:

Related Issues

N/A

Summary of Changes

• Updated runs-on labels across all workflow jobs to target the new self-hosted runner pools:
  • Docker build jobs (docker-build in ci.yml, push-operator-images in docker.yml) now run on dind-sm-standard-4.
  • All other jobs (skip-check, test-and-lint in ci.yml; build-helm-package, publish-helm-package in helm-package.yml) now run on sm-standard-2.

Checklist

• I have read and followed the CONTRIBUTING.md guidelines
• Passed make pre-commit (fmt-check + clippy + test + console-lint + console-fmt-check)
• Added/updated necessary tests — N/A (CI runner labels only)
• Documentation updated (if needed) — N/A
• CHANGELOG.md updated under [Unreleased] (if user-visible change) — N/A (not user-visible)
• CI/CD passed (if applicable)

Impact

• Breaking change (CRD/API compatibility)
• Requires doc/config/deployment update
• Other impact: CI jobs now require the dind-sm-standard-4 and sm-standard-2 self-hosted runners to be registered with the expected labels.

Verification

# YAML lint (self-hosted labels are expected to be unknown to actionlint's
# default label list; verified identical behavior on the previous labels):
python3 -c "import yaml,glob;[yaml.safe_load(open(f)) for f in glob.glob('.github/workflows/*.yml')]"

# Full local checks (passed with Helm 3.21.3 on PATH for tenant chart contract tests):
make pre-commit

Additional Notes

• Branched from latest main (a657983). No source code changes — only runs-on: labels in the three workflow files.