feat: Tauri desktop app scaffold

- src-tauri/ with Rust backend, Cargo.toml, main.rs, lib.rs
- tauri.conf.json: Linux deb bundle with webkit2gtk deps
- package.json: added tauri script
- Build on a machine with Rust: cd web && npm run tauri build

web/src-tauri/src/main.rs

@@ -0,0 +1,6 @@
+// Prevents additional console window on Windows in release, DO NOT REMOVE!!
+#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
+
+fn main() {
+  app_lib::run();
+}