fix(frontend): add .js extension to electron-log/main imports

Node.js ESM module resolution requires explicit file extensions for
package subpath imports. Since electron-log is externalized in the
vite config, it's resolved at runtime where ESM rules apply.

This fixes the ERR_MODULE_NOT_FOUND error when running dev mode.

apps/frontend/src/main/__tests__/app-logger.test.ts

@@ -18,7 +18,7 @@ const mockGetFile = vi.fn();
 const mockGetPath = vi.fn();
 
 // Mock electron-log before importing
-vi.mock('electron-log/main', () => ({
+vi.mock('electron-log/main.js', () => ({
   default: {
     initialize: vi.fn(),
     transports: {
@@ -433,7 +433,7 @@ describe('Application Logger', () => {
   describe('Beta version detection', () => {
     it('should detect beta version from app version', async () => {
       // The mock returns '2.7.2-beta.10' which should be detected as beta
-      const electronLog = await import('electron-log/main');
+      const electronLog = await import('electron-log/main.js');
 
       // Beta version should set file level to debug
       // This is tested implicitly by the mock setup

apps/frontend/src/main/__tests__/ipc-handlers.test.ts

@@ -57,7 +57,7 @@ vi.mock('../notification-service', () => ({
 }));
 
 // Mock electron-log to prevent Electron binary dependency
-vi.mock('electron-log/main', () => ({
+vi.mock('electron-log/main.js', () => ({
   default: {
     initialize: vi.fn(),
     transports: {

apps/frontend/src/main/app-logger.ts

@@ -14,7 +14,7 @@
  * - Beta version detection for enhanced logging
  */
 
-import log from 'electron-log/main';
+import log from 'electron-log/main.js';
 import { app } from 'electron';
 import { existsSync, readdirSync, statSync, readFileSync } from 'fs';
 import { join, dirname } from 'path';