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/workbox-google-analytics/initialize.d.ts

@@ -0,0 +1,26 @@
+import './_version.js';
+export interface GoogleAnalyticsInitializeOptions {
+    cacheName?: string;
+    parameterOverrides?: {
+        [paramName: string]: string;
+    };
+    hitFilter?: (params: URLSearchParams) => void;
+}
+/**
+ * @param {Object=} [options]
+ * @param {Object} [options.cacheName] The cache name to store and retrieve
+ *     analytics.js. Defaults to the cache names provided by `workbox-core`.
+ * @param {Object} [options.parameterOverrides]
+ *     [Measurement Protocol parameters](https://developers.google.com/analytics/devguides/collection/protocol/v1/parameters),
+ *     expressed as key/value pairs, to be added to replayed Google Analytics
+ *     requests. This can be used to, e.g., set a custom dimension indicating
+ *     that the request was replayed.
+ * @param {Function} [options.hitFilter] A function that allows you to modify
+ *     the hit parameters prior to replaying
+ *     the hit. The function is invoked with the original hit's URLSearchParams
+ *     object as its only argument.
+ *
+ * @memberof workbox-google-analytics
+ */
+declare const initialize: (options?: GoogleAnalyticsInitializeOptions) => void;
+export { initialize };