[Enhancement]: CI - Added Python test job for core/ and tools/

[Markolissimo]

Problem Statement

The CI workflow (.github/workflows/ci.yml) currently only runs Node.js tests (npm run lint/test/build) and Docker builds. However, this repository contains critical Python packages in core/ (framework) and tools/ (aden_tools) with test suites in core/tests/ and tools/tests/.
These Python tests are not executed in CI, which means:

• Python regressions can be merged undetected
• Contributors don't get immediate feedback on Python changes
• The test coverage shown in CI is incomplete

Proposed Solution

Add a new GitHub Actions job python-test that:

1. Sets up Python 3.11+
2. Installs core package with dev dependencies: pip install -e ./core[dev]
3. Installs tools package with dev dependencies: pip install -e ./tools[dev]
4. Runs pytest core/tests
5. Runs pytest tools/tests
6. Makes build and docker jobs depend on python-test passing

Acceptance Criteria

• CI runs Python tests on every PR
• Failing Python tests block the PR from merging
• Test results are visible in the GitHub Actions UI
• Python test job runs in parallel with Node lint/test jobs