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/paint-bucket.mjs

@@ -0,0 +1,31 @@
+/**
+ * @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: "M11 7 6 2", key: "1jwth8" }],
+  ["path", { d: "M18.992 12H2.041", key: "xw1gg" }],
+  [
+    "path",
+    {
+      d: "M21.145 18.38A3.34 3.34 0 0 1 20 16.5a3.3 3.3 0 0 1-1.145 1.88c-.575.46-.855 1.02-.855 1.595A2 2 0 0 0 20 22a2 2 0 0 0 2-2.025c0-.58-.285-1.13-.855-1.595",
+      key: "1nkol4"
+    }
+  ],
+  [
+    "path",
+    {
+      d: "m8.5 4.5 2.148-2.148a1.205 1.205 0 0 1 1.704 0l7.296 7.296a1.205 1.205 0 0 1 0 1.704l-7.592 7.592a3.615 3.615 0 0 1-5.112 0l-3.888-3.888a3.615 3.615 0 0 1 0-5.112L5.67 7.33",
+      key: "1nk1rd"
+    }
+  ]
+];
+const PaintBucket = createLucideIcon("paint-bucket", __iconNode);
+
+export { __iconNode, PaintBucket as default };
+//# sourceMappingURL=paint-bucket.mjs.map