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/@babel/runtime/helpers/esm/unsupportedIterableToArray.js

@@ -0,0 +1,9 @@
+import arrayLikeToArray from "./arrayLikeToArray.js";
+function _unsupportedIterableToArray(r, a) {
+  if (r) {
+    if ("string" == typeof r) return arrayLikeToArray(r, a);
+    var t = {}.toString.call(r).slice(8, -1);
+    return "Object" === t && r.constructor && (t = r.constructor.name), "Map" === t || "Set" === t ? Array.from(r) : "Arguments" === t || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(t) ? arrayLikeToArray(r, a) : void 0;
+  }
+}
+export { _unsupportedIterableToArray as default };