feat(ffmpeg): add ffmpeg manager, bundle/download ffmpeg in CI and (#11)

* feat(ffmpeg): add ffmpeg manager, bundle/download ffmpeg in CI and

* fix(download-engine): let yt-dlp merge format to avoid codec conflicts and use actual format for filenames

* chore(ci): replace monolithic job with platform-specific reusable jobs

* chore(ci): run build matrix for windows, macos, linux in one to

* feat(ci): remove platform matrix and platform gating to simplify build

* chore(ci): pin github-translate-action to specific commit to ensure

src/main/index.ts

@@ -7,6 +7,7 @@ import appIcon from '../../build/icon.png?asset'
 import { configureLogger } from './config/logger-config'
 import { services } from './ipc'
 import { downloadEngine } from './lib/download-engine'
+import { ffmpegManager } from './lib/ffmpeg-manager'
 import { ytdlpManager } from './lib/ytdlp-manager'
 import { settingsManager } from './settings'
 import { createTray, destroyTray } from './tray'
@@ -179,6 +180,15 @@ app.whenReady().then(async () => {
   // IPC services are automatically registered by electron-ipc-decorator when imported
   log.info('IPC services available:', Object.keys(services))
 
+  // Initialize ffmpeg
+  try {
+    log.info('Initializing ffmpeg...')
+    await ffmpegManager.initialize()
+    log.info('ffmpeg initialized successfully')
+  } catch (error) {
+    log.error('Failed to initialize ffmpeg:', error)
+  }
+
   // Initialize yt-dlp
   try {
     log.info('Initializing yt-dlp...')