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/dna.mjs

@@ -0,0 +1,26 @@
+/**
+ * @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 16 1.5 1.5", key: "11lckj" }],
+  ["path", { d: "m14 8-1.5-1.5", key: "1ohn8i" }],
+  ["path", { d: "M15 2c-1.798 1.998-2.518 3.995-2.807 5.993", key: "80uv8i" }],
+  ["path", { d: "m16.5 10.5 1 1", key: "696xn5" }],
+  ["path", { d: "m17 6-2.891-2.891", key: "xu6p2f" }],
+  ["path", { d: "M2 15c6.667-6 13.333 0 20-6", key: "1pyr53" }],
+  ["path", { d: "m20 9 .891.891", key: "3xwk7g" }],
+  ["path", { d: "M3.109 14.109 4 15", key: "q76aoh" }],
+  ["path", { d: "m6.5 12.5 1 1", key: "cs35ky" }],
+  ["path", { d: "m7 18 2.891 2.891", key: "1sisit" }],
+  ["path", { d: "M9 22c1.798-1.998 2.518-3.995 2.807-5.993", key: "q3hbxp" }]
+];
+const Dna = createLucideIcon("dna", __iconNode);
+
+export { __iconNode, Dna as default };
+//# sourceMappingURL=dna.mjs.map