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/pencil-sparkles.mjs

@@ -0,0 +1,29 @@
+/**
+ * @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: "M10 3H8", key: "mzdi2d" }],
+  ["path", { d: "m15.007 5.008 3.987 3.986", key: "1scubj" }],
+  ["path", { d: "M20 15v4", key: "nmhudv" }],
+  [
+    "path",
+    {
+      d: "M21.174 6.813a2.82 2.82 0 0 0-3.986-3.987L3.842 16.175a2 2 0 0 0-.5.83l-1.321 4.352a.5.5 0 0 0 .623.622l4.353-1.32a2 2 0 0 0 .83-.497z",
+      key: "fs0856"
+    }
+  ],
+  ["path", { d: "M22 17h-4", key: "1sj068" }],
+  ["path", { d: "M4 5v4", key: "13jjxc" }],
+  ["path", { d: "M6 7H2", key: "8zbtv0" }],
+  ["path", { d: "M9 2v2", key: "165o2o" }]
+];
+const PencilSparkles = createLucideIcon("pencil-sparkles", __iconNode);
+
+export { __iconNode, PencilSparkles as default };
+//# sourceMappingURL=pencil-sparkles.mjs.map