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/dist/esm/server/app-render/validate-url.js

@@ -0,0 +1,19 @@
+const DUMMY_ORIGIN = "http://n";
+const INVALID_URL_MESSAGE = "Invalid request URL";
+export function validateURL(url) {
+    if (!url) {
+        throw new Error(INVALID_URL_MESSAGE);
+    }
+    try {
+        const parsed = new URL(url, DUMMY_ORIGIN);
+        // Avoid origin change by extra slashes in pathname
+        if (parsed.origin !== DUMMY_ORIGIN) {
+            throw new Error(INVALID_URL_MESSAGE);
+        }
+        return url;
+    } catch  {
+        throw new Error(INVALID_URL_MESSAGE);
+    }
+}
+
+//# sourceMappingURL=validate-url.js.map