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/tinyglobby/README.md

@@ -0,0 +1,25 @@
+# tinyglobby
+
+[![npm version](https://img.shields.io/npm/v/tinyglobby.svg?maxAge=3600)](https://npmjs.com/package/tinyglobby)
+[![weekly downloads](https://img.shields.io/npm/dw/tinyglobby.svg?maxAge=3600)](https://npmjs.com/package/tinyglobby)
+
+A fast and minimal alternative to globby and fast-glob, meant to behave the same way.
+
+Both globby and fast-glob present some behavior no other globbing lib has,
+which makes it hard to manually replace with something smaller and better.
+
+This library uses only two subdependencies, compared to `globby`'s [23](https://npmgraph.js.org/?q=globby@16.2.0)
+and `fast-glob`'s [17](https://npmgraph.js.org/?q=fast-glob@3.3.3).
+
+## Usage
+
+```js
+import { glob, globSync } from 'tinyglobby';
+
+await glob(['files/*.ts', '!**/*.d.ts'], { cwd: 'src' });
+globSync('src/**/*.ts', { ignore: '**/*.d.ts' });
+```
+
+## Documentation
+
+Visit https://superchupu.dev/tinyglobby to read the full documentation.