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/bath.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: "M10 4 8 6", key: "1rru8s" }],
+  ["path", { d: "M17 19v2", key: "ts1sot" }],
+  ["path", { d: "M2 12h20", key: "9i4pu4" }],
+  ["path", { d: "M7 19v2", key: "12npes" }],
+  [
+    "path",
+    {
+      d: "M9 5 7.621 3.621A2.121 2.121 0 0 0 4 5v12a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2v-5",
+      key: "14ym8i"
+    }
+  ]
+];
+const Bath = createLucideIcon("bath", __iconNode);
+
+export { __iconNode, Bath as default };
+//# sourceMappingURL=bath.mjs.map