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/timeline.mjs

@@ -0,0 +1,41 @@
+/**
+ * @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: "M4 12h.01", key: "158zrr" }],
+  ["path", { d: "M4 16h.01", key: "jrnfb7" }],
+  ["path", { d: "M4 20h.01", key: "orx0iu" }],
+  ["path", { d: "M4 4h.01", key: "cieki8" }],
+  ["path", { d: "M4 8h.01", key: "43g258" }],
+  [
+    "path",
+    {
+      d: "M9.414 13.414a2 2 0 0 0 1.414.586H19a1 1 0 0 0 1-1v-2a1 1 0 0 0-1-1h-8.172a2 2 0 0 0-1.414.586L8 12z",
+      key: "1pvxkf"
+    }
+  ],
+  [
+    "path",
+    {
+      d: "M9.414 21.414a2 2 0 0 0 1.414.586H19a1 1 0 0 0 1-1v-2a1 1 0 0 0-1-1h-8.172a2 2 0 0 0-1.414.586L8 20z",
+      key: "1k13gh"
+    }
+  ],
+  [
+    "path",
+    {
+      d: "M9.414 5.414A2 2 0 0 0 10.828 6H19a1 1 0 0 0 1-1V3a1 1 0 0 0-1-1h-8.172a2 2 0 0 0-1.414.586L8 4z",
+      key: "12x0hd"
+    }
+  ]
+];
+const Timeline = createLucideIcon("timeline", __iconNode);
+
+export { __iconNode, Timeline as default };
+//# sourceMappingURL=timeline.mjs.map