feat(ai): add comprehensive quality test suite for core-ai agent

Add automated test suite for regression detection and performance tracking
of the core-ai agent behavior across code changes.

Changes:
- Add test_ai_flow_quality.py with 5 core test scenarios
  - Simple knowledge queries (no tools)
  - Web search integration
  - Mathematical calculations
  - Date/time operations
  - Multi-tool reasoning tasks
- Add QUALITY_TESTS.md documentation
  - Usage guide and test descriptions
  - Baseline establishment workflow
  - Model benchmarking procedures
  - Troubleshooting guide
- Add performance baseline tests
- Add regression detection tests
- Generate text and JSON reports with git tagging
- Update .gitignore to exclude generated test reports
- Update CHANGELOG.md with test suite details

Baseline Results:
- 4/5 tests passing (80% success rate)
- Average response time: 2-8s per query
- Agent: OllamaNativeAgent with PydanticAI
- Model: mistral-nemo:latest

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.gitignore

@@ -91,6 +91,7 @@ cache/
 coverage/
 .coverage
 test-results/
+services/core-ai/tests/reports/
 
 # Documentation builds
 docs/_build/