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/spotlight.mjs

@@ -0,0 +1,26 @@
+/**
+ * @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: "M15.295 19.562 16 22", key: "31jsb7" }],
+  ["path", { d: "m17 16 3.758 2.098", key: "121ar7" }],
+  ["path", { d: "m19 12.5 3.026-.598", key: "19ukd3" }],
+  [
+    "path",
+    {
+      d: "M7.61 6.3a3 3 0 0 0-3.92 1.3l-1.38 2.79a3 3 0 0 0 1.3 3.91l6.89 3.597a1 1 0 0 0 1.342-.447l3.106-6.211a1 1 0 0 0-.447-1.341z",
+      key: "lwb9l9"
+    }
+  ],
+  ["path", { d: "M8 9V2", key: "1xa0v7" }]
+];
+const Spotlight = createLucideIcon("spotlight", __iconNode);
+
+export { __iconNode, Spotlight as default };
+//# sourceMappingURL=spotlight.mjs.map