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/database-search.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: "M21 11.693V5", key: "175m1t" }],
+  ["path", { d: "m22 22-1.875-1.875", key: "13zax7" }],
+  ["path", { d: "M3 12a9 3 0 0 0 8.697 2.998", key: "151u9p" }],
+  ["path", { d: "M3 5v14a9 3 0 0 0 9.28 2.999", key: "q2rs2p" }],
+  ["circle", { cx: "18", cy: "18", r: "3", key: "1xkwt0" }],
+  ["ellipse", { cx: "12", cy: "5", rx: "9", ry: "3", key: "msslwz" }]
+];
+const DatabaseSearch = createLucideIcon("database-search", __iconNode);
+
+export { __iconNode, DatabaseSearch as default };
+//# sourceMappingURL=database-search.mjs.map