feat: FFmpeg GUI desktop application

Wails v2 + Vue3 + Go project with:
- Encode/Remux/Subtitle burn with hardware acceleration
- Real-time progress with ffmpeg stderr parsing (\r delimiter handling)
- Task queue with cancel support
- Per-task log viewer with color-coded output
- Custom frameless window with resize support
- Dark/light theme toggle
- Hardware encoder detection (NVENC/QSV/AMF)

wails.json

@@ -0,0 +1,13 @@
+{
+  "$schema": "https://wails.io/schemas/config.v2.json",
+  "name": "FFmpeg GUI",
+  "outputfilename": "ffmpeg-gui",
+  "frontend:install": "npm install",
+  "frontend:build": "npm run build",
+  "frontend:dev:watcher": "npm run dev",
+  "frontend:dev:serverUrl": "",
+  "author": {
+    "name": "sansen",
+    "email": ""
+  }
+}