fix: add missing type annotations in workflow diff tests

Resolved TypeScript implicit 'any' type errors identified during
code review for Phase 0 connection operations fixes.

Changes:
- Added type annotation to map callback parameters (lines 1003, 1115)
- All 126 tests still passing
- TypeScript compilation now clean

Related: Issue #272, #204
Code review: Phase 0 critical fixes implementation

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

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

tests/unit/services/workflow-diff-engine.test.ts

@@ -1000,7 +1000,7 @@ describe('WorkflowDiffEngine', () => {
       // So we expect 4 total connections
       const connectionsAtIndex0 = result.workflow!.connections['Webhook']['main'][0];
       expect(connectionsAtIndex0.length).toBeGreaterThanOrEqual(3);
-      const targets = connectionsAtIndex0.map(c => c.node);
+      const targets = connectionsAtIndex0.map((c: any) => c.node);
       expect(targets).toContain('Processor1');
       expect(targets).toContain('Processor2');
       expect(targets).toContain('Processor3');
@@ -1112,7 +1112,7 @@ describe('WorkflowDiffEngine', () => {
       expect(result.success).toBe(true);
       expect(result.workflow!.connections['Webhook']['main'][0]).toBeDefined();
       // TestNode should be in the connections (might not be first if HTTP Request already exists)
-      const targets = result.workflow!.connections['Webhook']['main'][0].map(c => c.node);
+      const targets = result.workflow!.connections['Webhook']['main'][0].map((c: any) => c.node);
       expect(targets).toContain('TestNode');
     });
   });