* feat: Add GitHub Actions workflows for security audits, CodeQL analysis, contributor updates, performance benchmarks, integration tests, fuzz testing, and reusable Rust build jobs
- Implemented `sec-audit.yml` for Rust package security audits using `rustsec/audit-check` and `cargo-deny-action`.
- Created `sec-codeql.yml` for CodeQL analysis scheduled twice daily.
- Added `sync-contributors.yml` to update the NOTICE file with new contributors automatically.
- Introduced `test-benchmarks.yml` for performance benchmarks using Criterion.
- Established `test-e2e.yml` for running integration and end-to-end tests.
- Developed `test-fuzz.yml` for fuzz testing with configurable runtime.
- Created `test-rust-build.yml` as a reusable job for executing Rust commands with customizable parameters.
- Documented main branch delivery flows in `main-branch-flow.md` for clarity on CI/CD processes.
* ci(workflows): update workflow scripts and rename for clarity; remove obsolete lint feedback script
* chore(ci): externalize workflow scripts and relocate main flow doc
Add blacksmith-2vcpu-ubuntu-2404 to actionlint self-hosted-runner labels config
to suppress "unknown label" warnings during workflow linting.
This label is used across all workflows after the Blacksmith migration.
Add actionlint.yaml config to declare lxc-ci as a known custom label
for self-hosted runners, fixing the actionlint CI check.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>