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/hat-glasses.mjs

@@ -0,0 +1,26 @@
+/**
+ * @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: "M14 18a2 2 0 0 0-4 0", key: "1v8fkw" }],
+  [
+    "path",
+    {
+      d: "m19 11-2.11-6.657a2 2 0 0 0-2.752-1.148l-1.276.61A2 2 0 0 1 12 4H8.5a2 2 0 0 0-1.925 1.456L5 11",
+      key: "1fkr7p"
+    }
+  ],
+  ["path", { d: "M2 11h20", key: "3eubbj" }],
+  ["circle", { cx: "17", cy: "18", r: "3", key: "82mm0e" }],
+  ["circle", { cx: "7", cy: "18", r: "3", key: "lvkj7j" }]
+];
+const HatGlasses = createLucideIcon("hat-glasses", __iconNode);
+
+export { __iconNode, HatGlasses as default };
+//# sourceMappingURL=hat-glasses.mjs.map