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/autoprefixer/lib/hacks/grid-start.js

@@ -0,0 +1,33 @@
+let Declaration = require('../declaration')
+
+class GridStart extends Declaration {
+  /**
+   * Do not add prefix for unsupported value in IE
+   */
+  check(decl) {
+    let value = decl.value
+    return !value.includes('/') && !value.includes('span')
+  }
+
+  /**
+   * Return a final spec property
+   */
+  normalize(prop) {
+    return prop.replace('-start', '')
+  }
+
+  /**
+   * Change property name for IE
+   */
+  prefixed(prop, prefix) {
+    let result = super.prefixed(prop, prefix)
+    if (prefix === '-ms-') {
+      result = result.replace('-start', '')
+    }
+    return result
+  }
+}
+
+GridStart.names = ['grid-row-start', 'grid-column-start']
+
+module.exports = GridStart