Rewrite web frontend to pure Rust

[tommythorn]

Maintaining the Javascript frontend is awkward for me and clearly it’s starting to bitrot. I have some initial work that keeps the non-Rust parts at a bare minimum (on the order of four lines), but the terminal emulation would have to be implemented, though I suspect we don’t need to fully replicate xterm.js.

[tommythorn]

Part of this should fix the behavior on mobile where the terminal is near-unreadable; it should expand to the full width of the display and not use more than 80 columns.

[tommythorn]

Some links I found relevant:

• https://github.com/wasm-bindgen/wasm-bindgen/tree/main/examples/without-a-bundler
• https://gitlab.com/limira-rs/wasm-logger/-/tree/master/examples/log
• https://www.reddit.com/r/rust/comments/xbr6m7/wasm_pointing_the_log_to_the_browser_console/
• https://github.com/tommythorn/pure_rust_wasm_app
• https://github.com/tommythorn/pure-rust-wasm-gfx

[tommythorn]

https://github.com/tommythorn/wemur was a design study for this and quite successful, so this issue now is really about replacing the current wasm work with wemur. However, wemur is bitmap framebuffer based; probably the best path forward (for now) is to just emulate a fairly minimal terminal and render the font directly to the framebuffer, leave the path open for exposing the frame buffer to Linux down the line.