Add sync error logging, extend error flash, fix unload saves

- Log workforce sync errors to backend stdout so they appear in docker logs
- Extend error flash from 5s to 15s so errors are readable
- Replace sendBeacon (POST-only) with keepalive fetch (PUT) on unload —
  sendBeacon was hitting 404s on all three unload saves

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/node_modules/lucide-react/dist/esm/icons/mouse-pointer-ban.mjs

@@ -0,0 +1,24 @@
+/**
+ * @license lucide-react v1.24.0 - ISC
+ *
+ * This source code is licensed under the ISC license.
+ * See the LICENSE file in the root directory of this source tree.
+ */
+
+import createLucideIcon from '../createLucideIcon.mjs';
+
+const __iconNode = [
+  [
+    "path",
+    {
+      d: "M2.034 2.681a.498.498 0 0 1 .647-.647l9 3.5a.5.5 0 0 1-.033.944L8.204 7.545a1 1 0 0 0-.66.66l-1.066 3.443a.5.5 0 0 1-.944.033z",
+      key: "11pp1i"
+    }
+  ],
+  ["circle", { cx: "16", cy: "16", r: "6", key: "qoo3c4" }],
+  ["path", { d: "m11.8 11.8 8.4 8.4", key: "oogvdj" }]
+];
+const MousePointerBan = createLucideIcon("mouse-pointer-ban", __iconNode);
+
+export { __iconNode, MousePointerBan as default };
+//# sourceMappingURL=mouse-pointer-ban.mjs.map