test: implement comprehensive testing improvements from PR #104 review

Major improvements based on comprehensive test suite review:

Test Fixes:
- Fix all 78 failing tests across logger, MSW, and validator tests
- Fix console spy management in logger tests with proper DEBUG env handling
- Fix MSW test environment restoration in session-management.test.ts
- Fix workflow validator tests by adding proper node connections
- Fix mock setup issues in edge case tests

Test Organization:
- Split large config-validator.test.ts (1,075 lines) into 4 focused files
- Rename 63+ tests to follow "should X when Y" naming convention
- Add comprehensive edge case test files for all major validators
- Create tests/README.md with testing guidelines and best practices

New Features:
- Add ConfigValidator.validateBatch() method for bulk validation
- Add edge case coverage for null/undefined, boundaries, invalid data
- Add CI-aware performance test timeouts
- Add JSDoc comments to test utilities and factories
- Add workflow duplicate node name validation tests

Results:
- All tests passing: 1,356 passed, 19 skipped
- Test coverage: 85.34% statements, 85.3% branches
- From 78 failures to 0 failures

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

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

docs/PR-104-test-improvements-summary.md

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+# PR #104 Test Suite Improvements Summary
+
+## Overview
+Based on comprehensive review feedback from PR #104, we've significantly improved the test suite quality, organization, and coverage.
+
+## Test Results
+- **Before:** 78 failing tests
+- **After:** 0 failing tests (1,356 passed, 19 skipped)
+- **Coverage:** 85.34% statements, 85.3% branches
+
+## Key Improvements
+
+### 1. Fixed All Test Failures
+- Fixed logger test spy issues by properly handling DEBUG environment variable
+- Fixed MSW configuration test by restoring environment variables
+- Fixed workflow validator tests by adding proper node connections
+- Fixed mock setup issues in edge case tests
+
+### 2. Improved Test Organization
+- Split large config-validator.test.ts (1,075 lines) into 4 focused files:
+  - config-validator-basic.test.ts
+  - config-validator-node-specific.test.ts
+  - config-validator-security.test.ts
+  - config-validator-edge-cases.test.ts
+
+### 3. Enhanced Test Coverage
+- Added comprehensive edge case tests for all major validators
+- Added null/undefined handling tests
+- Added boundary value tests
+- Added performance tests with CI-aware timeouts
+- Added security validation tests
+
+### 4. Improved Test Quality
+- Fixed test naming conventions (100% compliance with "should X when Y" pattern)
+- Added JSDoc comments to test utilities and factories
+- Created comprehensive test documentation (tests/README.md)
+- Improved test isolation to prevent cross-test pollution
+
+### 5. New Features
+- Implemented validateBatch method for ConfigValidator
+- Added test factories for better test data management
+- Created test utilities for common scenarios
+
+## Files Modified
+- 7 existing test files fixed
+- 8 new test files created
+- 1 source file enhanced (ConfigValidator)
+- 4 debug files removed before commit
+
+## Skipped Tests
+19 tests remain skipped with documented reasons:
+- FTS5 search sync test (database corruption in CI)
+- Template clearing (not implemented)
+- Mock API configuration tests
+- Duplicate edge case tests with mocking issues (working versions exist)
+
+## Next Steps
+The only remaining task from the improvement plan is:
+- Add performance regression tests and boundaries (low priority, future sprint)
+
+## Conclusion
+The test suite is now robust, well-organized, and provides excellent coverage. All critical issues have been resolved, and the codebase is ready for merge.