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/dam.mjs

@@ -0,0 +1,28 @@
+/**
+ * @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 11.31c1.17.56 1.54 1.69 3.5 1.69 2.5 0 2.5-2 5-2 1.3 0 1.9.5 2.5 1", key: "157kva" }
+  ],
+  ["path", { d: "M11.75 18c.35.5 1.45 1 2.75 1 2.5 0 2.5-2 5-2 1.3 0 1.9.5 2.5 1", key: "d7q6m6" }],
+  ["path", { d: "M2 10h4", key: "l0bgd4" }],
+  ["path", { d: "M2 14h4", key: "1gsvsf" }],
+  ["path", { d: "M2 18h4", key: "1bu2t1" }],
+  ["path", { d: "M2 6h4", key: "aawbzj" }],
+  [
+    "path",
+    { d: "M7 3a1 1 0 0 0-1 1v16a1 1 0 0 0 1 1h4a1 1 0 0 0 1-1L10 4a1 1 0 0 0-1-1z", key: "pr6s65" }
+  ]
+];
+const Dam = createLucideIcon("dam", __iconNode);
+
+export { __iconNode, Dam as default };
+//# sourceMappingURL=dam.mjs.map