Improvement: Integration tests baseline for feature verification

> [!IMPORTANT]
> Make sure to link this issue with the PR for your improvement.

Purpose
- Deliver a repository-level, executable integration-test baseline that validates the implemented feature scope and provides maintainable automated tests.

Scope
- Consolidate and formalize already implemented feature verification test cases into maintainable repository-level integration tests.
- Cover repository-executable verification scenarios for the implemented functionality,
- Introduce a CI-workflow baseline that automatically builds and runs the `score_time` integration-test

Deliverables
- Component Integration Tests for `time_daemon` and `time_slave` via the repository's CI/test runner.
- Module Integration Tests across slave and daemon via the repository's CI/test runner.
- System Integration Tests running in Docker (Linux) and QEMU (QNX) via the repository's CI/test runner.。

Acceptance criteria
- Repository-level integration tests execute locally and in CI. Test passes.