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/person-standing.mjs

@@ -0,0 +1,19 @@
+/**
+ * @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 = [
+  ["circle", { cx: "12", cy: "5", r: "1", key: "gxeob9" }],
+  ["path", { d: "m9 20 3-6 3 6", key: "se2kox" }],
+  ["path", { d: "m6 8 6 2 6-2", key: "4o3us4" }],
+  ["path", { d: "M12 10v4", key: "1kjpxc" }]
+];
+const PersonStanding = createLucideIcon("person-standing", __iconNode);
+
+export { __iconNode, PersonStanding as default };
+//# sourceMappingURL=person-standing.mjs.map