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/@babel/helper-module-imports/lib/index.js

@@ -0,0 +1,37 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+Object.defineProperty(exports, "ImportInjector", {
+  enumerable: true,
+  get: function () {
+    return _importInjector.default;
+  }
+});
+exports.addDefault = addDefault;
+exports.addNamed = addNamed;
+exports.addNamespace = addNamespace;
+exports.addSideEffect = addSideEffect;
+Object.defineProperty(exports, "isModule", {
+  enumerable: true,
+  get: function () {
+    return _isModule.default;
+  }
+});
+var _importInjector = require("./import-injector.js");
+var _isModule = require("./is-module.js");
+function addDefault(path, importedSource, opts) {
+  return new _importInjector.default(path).addDefault(importedSource, opts);
+}
+function addNamed(path, name, importedSource, opts) {
+  return new _importInjector.default(path).addNamed(name, importedSource, opts);
+}
+function addNamespace(path, importedSource, opts) {
+  return new _importInjector.default(path).addNamespace(importedSource, opts);
+}
+function addSideEffect(path, importedSource, opts) {
+  return new _importInjector.default(path).addSideEffect(importedSource, opts);
+}
+
+//# sourceMappingURL=index.js.map