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/toPrimitive.js

@@ -0,0 +1,12 @@
+var _typeof = require("./typeof.js")["default"];
+function toPrimitive(t, r) {
+  if ("object" != _typeof(t) || !t) return t;
+  var e = t[Symbol.toPrimitive];
+  if (void 0 !== e) {
+    var i = e.call(t, r || "default");
+    if ("object" != _typeof(i)) return i;
+    throw new TypeError("@@toPrimitive must return a primitive value.");
+  }
+  return ("string" === r ? String : Number)(t);
+}
+module.exports = toPrimitive, module.exports.__esModule = true, module.exports["default"] = module.exports;