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>

tests/unit/test-env-example.test.ts

@@ -7,7 +7,8 @@ import {
   getTestConfig, 
   getTestTimeout, 
   isFeatureEnabled,
-  isTestMode 
+  isTestMode,
+  loadTestEnvironment 
 } from '@tests/setup/test-env';
 import {
   withEnvOverrides,
@@ -189,6 +190,11 @@ describe('Test Environment Configuration Example', () => {
   });
   
   it('should support MSW configuration', () => {
+    // Ensure test environment is loaded
+    if (!process.env.MSW_ENABLED) {
+      loadTestEnvironment();
+    }
+    
     const testConfig = getTestConfig();
     expect(testConfig.mocking.msw.enabled).toBe(true);
     expect(testConfig.mocking.msw.apiDelay).toBe(0);