feat: add QR code generator and Nostr event handling

- Added the `simplesoftwareio/simple-qrcode` package to the project
- Created a new JavaScript file `nostrZap.js` to handle Nostr events
- Added the `nostrZap` function to the Alpine.js data property in `app.js`
- Updated the `services.php` configuration file to include the `nostr` environment variable
- Created a new database migration to add a `payment_event` field to the `einundzwanzig_plebs` table
- Made adjustments in the `Election:year.blade.php` view file to handle potential null values
- Updated `composer.lock` and `package.json` with the new dependencies

composer.json

@@ -23,6 +23,7 @@
         "livewire/volt": "^1.6",
         "openspout/openspout": "^4.24",
         "power-components/livewire-powergrid": "^5.10",
+        "simplesoftwareio/simple-qrcode": "^4.2",
         "spatie/image": "^3.7",
         "spatie/laravel-google-fonts": "^1.4",
         "spatie/laravel-medialibrary": "^11.9",