Add tm_server with SQLite, Svelte UI, and task-master TUI sync.

Introduces the web backend (auth, RBAC, project tokens, revisions),
YouTrack-or-taskmaster backend choice in the TUI, and a first-pass
embedded Svelte UI. The frontend is functional but needs a major rework.

Co-authored-by: Cursor <cursoragent@cursor.com>

web/src/main.js

@@ -0,0 +1,5 @@
+import { mount } from 'svelte'
+import './app.css'
+import App from './App.svelte'
+
+mount(App, { target: document.getElementById('app') })