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/@next/env/dist/index.d.ts

@@ -0,0 +1,20 @@
+export type Env = {
+    [key: string]: string | undefined;
+};
+export type LoadedEnvFiles = Array<{
+    path: string;
+    contents: string;
+}>;
+export declare let initialEnv: Env | undefined;
+export declare function updateInitialEnv(newEnv: Env): void;
+type Log = {
+    info: (...args: any[]) => void;
+    error: (...args: any[]) => void;
+};
+export declare function processEnv(loadedEnvFiles: LoadedEnvFiles, dir?: string, log?: Log, forceReload?: boolean, onReload?: (envFilePath: string) => void): Env;
+export declare function resetEnv(): void;
+export declare function loadEnvConfig(dir: string, dev?: boolean, log?: Log, forceReload?: boolean, onReload?: (envFilePath: string) => void): {
+    combinedEnv: Env;
+    loadedEnvFiles: LoadedEnvFiles;
+};
+export {};