Add TCK CI workflow, SUT start/stop scripts, and compliance docs

[MisterVVP]

Motivation

• Establish automated TCK (Technology Compatibility Kit) conformance checks for the project and provide deterministic SUT lifecycle management for CI runs.
• Document local reproduction steps so contributors can run the same TCK flow locally and produce the expected artifacts.

Description

• Add a GitHub Actions workflow at .github/workflows/tck.yml that runs on pull_request, push to main, and workflow_dispatch, builds dependencies, starts a deterministic SUT, runs the TCK mandatory category against 127.0.0.1:50061, collects diagnostics, and uploads artifacts.
• Add scripts/run_tck_sut.sh to build the project with cmake/Ninja, start the configured SUT binary, wait for readiness, and write PID/log files.
• Add scripts/stop_tck_sut.sh to stop the running SUT gracefully (with fallback to SIGKILL) and clean up the PID file.
• Extend docs/compliance/README.md with local reproduction instructions and a list of expected artifacts produced by the workflow.

Testing

• No automated tests were executed as part of this change; the new workflow will run on PRs and pushes to main to perform the TCK runs.
• The workflow is configured to run the TCK mandatory category and upload tck-artifacts and build-tck/tck-sut.log as artifacts when executed.

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Codex Task