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/map-pin-x.mjs

@@ -0,0 +1,25 @@
+/**
+ * @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: "M19.752 11.901A7.78 7.78 0 0 0 20 10a8 8 0 0 0-16 0c0 4.993 5.539 10.193 7.399 11.799a1 1 0 0 0 1.202 0 19 19 0 0 0 .09-.077",
+      key: "y0ewhp"
+    }
+  ],
+  ["circle", { cx: "12", cy: "10", r: "3", key: "ilqhr7" }],
+  ["path", { d: "m21.5 15.5-5 5", key: "11iqnx" }],
+  ["path", { d: "m21.5 20.5-5-5", key: "1bylgx" }]
+];
+const MapPinX = createLucideIcon("map-pin-x", __iconNode);
+
+export { __iconNode, MapPinX as default };
+//# sourceMappingURL=map-pin-x.mjs.map