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/bot-off.mjs

@@ -0,0 +1,22 @@
+/**
+ * @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: "M13.67 8H18a2 2 0 0 1 2 2v4.33", key: "7az073" }],
+  ["path", { d: "M2 14h2", key: "vft8re" }],
+  ["path", { d: "M20 14h2", key: "4cs60a" }],
+  ["path", { d: "M22 22 2 2", key: "1r8tn9" }],
+  ["path", { d: "M8 8H6a2 2 0 0 0-2 2v8a2 2 0 0 0 2 2h12a2 2 0 0 0 1.414-.586", key: "s09a7a" }],
+  ["path", { d: "M9 13v2", key: "rq6x2g" }],
+  ["path", { d: "M9.67 4H12v2.33", key: "110xot" }]
+];
+const BotOff = createLucideIcon("bot-off", __iconNode);
+
+export { __iconNode, BotOff as default };
+//# sourceMappingURL=bot-off.mjs.map