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/mic-off.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: "M12 19v3", key: "npa21l" }],
+  ["path", { d: "M15 9.34V5a3 3 0 0 0-5.68-1.33", key: "1gzdoj" }],
+  ["path", { d: "M16.95 16.95A7 7 0 0 1 5 12v-2", key: "cqa7eg" }],
+  ["path", { d: "M18.89 13.23A7 7 0 0 0 19 12v-2", key: "16hl24" }],
+  ["path", { d: "m2 2 20 20", key: "1ooewy" }],
+  ["path", { d: "M9 9v3a3 3 0 0 0 5.12 2.12", key: "r2i35w" }]
+];
+const MicOff = createLucideIcon("mic-off", __iconNode);
+
+export { __iconNode, MicOff as default };
+//# sourceMappingURL=mic-off.mjs.map