Add initial GUI plan outlining framework and architecture

GUI plan.md

@@ -0,0 +1,26 @@
+### Python-first
+
+- Primary GUI framework: `PySide6` (Qt for Python) — native desktop look, cross-platform on Windows and Linux, mature widget set, good documentation.
+- Desktop architecture: keep the core downloader logic as a Python package and expose a local HTTP/WebSocket API (e.g., `FastAPI`) that the GUI talks to. The GUI stays a thin client that issues commands and receives status updates.
+
+### Why this approach
+
+- Stay in Python end-to-end for now, minimizing new languages or runtimes.
+- A local API boundary lets you reuse the same backend for a future Web frontend (React/Next.js or plain SPA) and for Android (native or Flutter shell that talks to the API or a hosted API).
+- `PySide6` provides a polished native desktop UX and easier packaging for Windows/Linux compared with Python mobile toolkits.
+
+### Packaging & Distribution (brief)
+
+- Bundle the backend and GUI into one distributable. The GUI should spawn the local API process (background subprocess) on startup.
+- Windows: use `pyinstaller` or `briefcase` to create an executable/installer. Consider creating an MSI or Inno Setup installer for a polished UX.
+- Linux: provide AppImage, Snap, or distribution-specific packages (deb/rpm) — AppImage is a good starting point for single-file distribution.
+- Security: bind the local API to `localhost` only, use a short-lived token or IPC for authentication between GUI and backend, and avoid exposing unnecessary ports.
+
+### Roadmap (GUI → Web → Mobile)
+
+1. Desktop prototype: `FastAPI` backend + `PySide6` GUI (thin client) with basic playlist add/update/download controls and status streaming.
+2. Packaging: create Windows exe/installer and Linux AppImage for the prototype.
+3. Web frontend: build a web SPA that consumes the same backend API (hosted or local) — this reuses business logic with minimal change.
+4. Android: either a native app or cross-platform UI (Flutter/React Native) that calls the backend API; alternatively host the backend and make a thin mobile client.
+
+If you want, I can now: scaffold a minimal `FastAPI` backend and `PySide6` desktop starter in this repo, or produce concise packaging steps for Windows and Linux. Which do you prefer? 

project plan.md

@@ -38,6 +38,7 @@ Individuals who need to download a large number of videos or audio files from a
 - Allows adjusting all settings from the GUI
 - Modern Design
 
+
 ## Platform
 
 - Desktop application
@@ -51,4 +52,4 @@ Individuals who need to download a large number of videos or audio files from a
   - Python
 - Frontend
   - qt ?
-  - Tkinter?
+  - Tkinter?