fix: TypeScript compilation errors in test-automator generated tests

Fixed 29 TypeScript compilation errors in test files:

**breaking-change-detector.test.ts** (22 errors):
- Added missing `nodeType`, `fromVersion`, `toVersion` to BreakingChange objects
- All 22 BreakingChange object instantiations now comply with interface

**node-migration-service.test.ts** (3 errors):
- Added type assertions for dynamic property assignment in tests
- Lines 310, 396, 519: `(node as any).property = value`

**workflow-versioning-service.test.ts** (5 errors):
- Fixed N8nApiClient constructor: takes config object, not separate params
- Fixed updateWorkflow mock: returns Workflow object, not undefined

All tests now compile successfully with `npm run typecheck`.

Conceived by Romuald Członkowski - www.aiadvisors.pl/en

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

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

tests/unit/services/node-migration-service.test.ts

@@ -307,7 +307,7 @@ describe('NodeMigrationService', () => {
   describe('removeProperty migration', () => {
     it('should remove deprecated property', async () => {
       const node = createMockNode('node-1', 'nodes-base.httpRequest', 1, {});
-      node.oldField = 'value';
+      (node as any).oldField = 'value';
 
       const mockAnalysis: VersionUpgradeAnalysis = {
         nodeType: 'nodes-base.httpRequest',
@@ -393,7 +393,7 @@ describe('NodeMigrationService', () => {
   describe('renameProperty migration', () => {
     it('should rename property', async () => {
       const node = createMockNode('node-1', 'nodes-base.httpRequest', 1, {});
-      node.oldName = 'value';
+      (node as any).oldName = 'value';
 
       const mockAnalysis: VersionUpgradeAnalysis = {
         nodeType: 'nodes-base.httpRequest',
@@ -516,7 +516,7 @@ describe('NodeMigrationService', () => {
 
     it('should not overwrite existing value', async () => {
       const node = createMockNode('node-1', 'nodes-base.httpRequest', 1, {});
-      node.field = 'existing';
+      (node as any).field = 'existing';
 
       const mockAnalysis: VersionUpgradeAnalysis = {
         nodeType: 'nodes-base.httpRequest',