Remove In-Browser Frontend

[ThePerfectComputer]

Full browser support is eventually planned, but the implementation would look like the following:

1. The Moon backend would effectively contain almost all the logic currently in src-tauri/src/lib.rs
2. Just enough state would be shuttled to the frontend to maintain the illusion of a smooth user interface experience for the frontend user.

With this in mind, we can abort current development efforts on the fully in-browser frontend(which effectively also embeds Wellen into the frontend).

Furthermore, we should probably remove the code for this frontend from the codebase.