fix: removed duplicated type declarations

tests/renderer/types/electronApiContract.test.ts

@@ -0,0 +1,9 @@
+import { describe, it, expectTypeOf } from 'vitest';
+import type { ElectronAPI as SharedElectronAPI } from '../../../src/main/shared/electronApi';
+import type { ElectronAPI as RendererElectronAPI } from '../../../src/renderer/types/electron';
+
+describe('Electron API type contract', () => {
+  it('keeps renderer and shared ElectronAPI contracts in sync', () => {
+    expectTypeOf<RendererElectronAPI>().toEqualTypeOf<SharedElectronAPI>();
+  });
+});