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)

.gitignore

@@ -0,0 +1,31 @@
+# Dependencies
+frontend/node_modules/
+
+# Build output
+frontend/dist/
+FFmpeg_GUI-res.syso
+
+# ffmpeg binaries (large, not in repo)
+build/bin/ffmpeg*
+build/bin/ffprobe*
+
+# IDE
+.idea/
+*.iml
+.vscode/
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Go
+*.exe
+*.test
+*.out
+
+# Wails generated
+frontend/wailsjs/
+frontend/package.json.md5
+
+# Debug
+__debug_bin*