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/saudi-riyal.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 = [
+  ["path", { d: "m20 19.5-5.5 1.2", key: "1aenhr" }],
+  ["path", { d: "M14.5 4v11.22a1 1 0 0 0 1.242.97L20 15.2", key: "2rtezt" }],
+  ["path", { d: "m2.978 19.351 5.549-1.363A2 2 0 0 0 10 16V2", key: "1kbm92" }],
+  ["path", { d: "M20 10 4 13.5", key: "8nums9" }]
+];
+const SaudiRiyal = createLucideIcon("saudi-riyal", __iconNode);
+
+export { __iconNode, SaudiRiyal as default };
+//# sourceMappingURL=saudi-riyal.mjs.map