Cut over-engineering found by a repo-wide audit

- Config: auth, services, logging, queue and database only repeated the
  framework's own files and are gone; the others keep only the keys that
  differ (app version, cache serializable_classes, session cookie name,
  Markdown mail theme, the shares disk, three Octane values, Livewire's
  pagination theme and payload guards).
- Email verification is removed: User never implemented MustVerifyEmail,
  so it was never enforced, and SealShare has a single admin and no
  registration. CreateNewUser goes with it.
- FileEncryptionService::encryptFile() and generateSalt() were only used
  by tests; tests build files with encryptTestFile() in tests/Pest.php.
- The expiration options are defined once, as Share::EXPIRATIONS. "30 Days"
  now lasts 30 days instead of a calendar month, and Admin settings only
  save a default expiration that is one of the options.
- One-caller helpers are inlined, the uploader reads chunk responses with
  XHR's responseType, and starter-kit leftovers are removed.
- Docker: PHP reads the PHP_* limits from the environment itself
  (${VAR:-default} in uploads.ini); both entrypoints stop writing the ini.
  docker-compose.yml shares the app and scheduler variables through one
  anchor. The dev image installs gd for the screenshot publisher and fake
  test images.
- Development runs in Docker only: the composer dev script, concurrently,
  laravel/pail, laravel/sail, autoprefixer and the shell-quote override
  are gone.
- phpunit.xml forces the test environment with <server> entries, so tests
  run in the dev container no longer use its real database.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

app/Livewire/Admin/AdminSettings.php

@@ -3,6 +3,7 @@
 namespace App\Livewire\Admin;
 
 use App\Models\Setting;
+use App\Models\Share;
 use App\Services\PasswordGeneratorService;
 use Illuminate\Support\Facades\Hash;
 use Illuminate\Support\Facades\Storage;
@@ -92,6 +93,7 @@ class AdminSettings extends Component
     {
         $validated = $this->validate([
             'colorProfile' => ['required', 'string', Rule::in(array_keys(Scheme::profiles()))],
+            'defaultExpiration' => ['nullable', 'string', Rule::in(array_keys(Share::EXPIRATIONS))],
             'maxFileSize' => ['required', 'integer', 'min:1'],
             'maxStorageQuota' => ['required', 'integer', 'min:1'],
             'maxFilesPerShare' => ['required', 'integer', 'min:1'],
@@ -101,7 +103,7 @@ class AdminSettings extends Component
             'siteLogo' => ['nullable', 'file', 'mimes:png,jpg,jpeg,gif,webp', 'max:2048'],
             ...$this->passwordGeneratorRules(),
         ], [
-            ...$this->passwordGeneratorMessages(),
+            'passwordCharacterSets.required' => __('Choose at least one kind of character.'),
         ]);
 
         if ($this->systemPassword) {
@@ -160,16 +162,6 @@ class AdminSettings extends Component
         ];
     }
 
-    /**
-     * @return array<string, string>
-     */
-    protected function passwordGeneratorMessages(): array
-    {
-        return [
-            'passwordCharacterSets.required' => __('Choose at least one kind of character.'),
-        ];
-    }
-
     /**
      * Store the generator settings that passed validation; excluded ones keep their saved value.
      *