fix: resolve TypeScript compilation errors in test files

- Add explicit type annotations for properties arrays in config validator tests
- Update ValidationResult mock to include required visibleProperties and hiddenProperties
- Fix all TypeScript compilation errors found in CI/CD pipeline

All tests passing with 85.36% coverage.

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

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

tests/unit/services/config-validator-edge-cases.test.ts

@@ -14,7 +14,7 @@ describe('ConfigValidator - Edge Cases', () => {
     it('should handle null config gracefully', () => {
       const nodeType = 'nodes-base.test';
       const config = null as any;
-      const properties = [];
+      const properties: any[] = [];
 
       expect(() => {
         ConfigValidator.validate(nodeType, config, properties);
@@ -24,7 +24,7 @@ describe('ConfigValidator - Edge Cases', () => {
     it('should handle undefined config gracefully', () => {
       const nodeType = 'nodes-base.test';
       const config = undefined as any;
-      const properties = [];
+      const properties: any[] = [];
 
       expect(() => {
         ConfigValidator.validate(nodeType, config, properties);