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/scroll-text.mjs

@@ -0,0 +1,25 @@
+/**
+ * @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: "M15 12h-5", key: "r7krc0" }],
+  ["path", { d: "M15 8h-5", key: "1khuty" }],
+  ["path", { d: "M19 17V5a2 2 0 0 0-2-2H4", key: "zz82l3" }],
+  [
+    "path",
+    {
+      d: "M8 21h12a2 2 0 0 0 2-2v-1a1 1 0 0 0-1-1H11a1 1 0 0 0-1 1v1a2 2 0 1 1-4 0V5a2 2 0 1 0-4 0v2a1 1 0 0 0 1 1h3",
+      key: "1ph1d7"
+    }
+  ]
+];
+const ScrollText = createLucideIcon("scroll-text", __iconNode);
+
+export { __iconNode, ScrollText as default };
+//# sourceMappingURL=scroll-text.mjs.map