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/bird.mjs

@@ -0,0 +1,21 @@
+/**
+ * @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: "M16 7h.01", key: "1kdx03" }],
+  ["path", { d: "M3.4 18H12a8 8 0 0 0 8-8V7a4 4 0 0 0-7.28-2.3L2 20", key: "oj1oa8" }],
+  ["path", { d: "m20 7 2 .5-2 .5", key: "12nv4d" }],
+  ["path", { d: "M10 18v3", key: "1yea0a" }],
+  ["path", { d: "M14 17.75V21", key: "1pymcb" }],
+  ["path", { d: "M7 18a6 6 0 0 0 3.84-10.61", key: "1npnn0" }]
+];
+const Bird = createLucideIcon("bird", __iconNode);
+
+export { __iconNode, Bird as default };
+//# sourceMappingURL=bird.mjs.map