Add side panels, task selection, graph animation, and project docs

- Foldable left panel (user profile) and right panel (task details)
- Clicking a task in the list or graph node selects it and shows details
- Both views (task list + graph) always mounted via absolute inset-0 for
  correct canvas dimensions; tabs toggle visibility with opacity
- Graph node selection animation: other nodes repel outward (charge -600),
  then selected node smoothly slides to center (500ms cubic ease-out),
  then charge restores to -120 and graph stabilizes
- Graph re-fits on tab switch and panel resize via ResizeObserver
- Fix UUID string IDs throughout (backend returns UUIDs, not integers)
- Add TaskDetailPanel, UserPanel components
- Add CLAUDE.md project documentation

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/node_modules/tailwindcss/plugin.d.ts

@@ -0,0 +1,11 @@
+import type { Config, PluginCreator } from './types/config'
+type Plugin = {
+  withOptions<T>(
+    plugin: (options: T) => PluginCreator,
+    config?: (options: T) => Partial<Config>
+  ): { (options: T): { handler: PluginCreator; config?: Partial<Config> }; __isOptionsFunction: true }
+  (plugin: PluginCreator, config?: Partial<Config>): { handler: PluginCreator; config?: Partial<Config> }
+}
+
+declare const plugin: Plugin
+export = plugin