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>

tests/Feature/ShareDownloadTest.php

@@ -3,7 +3,6 @@
 use App\Livewire\ShareDownload;
 use App\Models\Share;
 use App\Models\ShareFile;
-use App\Services\FileEncryptionService;
 use App\Services\ShareService;
 use Illuminate\Http\UploadedFile;
 use Illuminate\Support\Facades\Storage;
@@ -280,7 +279,7 @@ test('a password share created before key wrapping still unlocks and downloads',
     $source = tempnam(sys_get_temp_dir(), 'old');
     file_put_contents($source, 'old content');
     Storage::disk('shares')->makeDirectory($share->token);
-    app(FileEncryptionService::class)->encryptFile($source, Storage::disk('shares')->path($share->token.'/old.enc'), bin2hex(hash_pbkdf2('sha256', 'old-password', hex2bin($salt), 100000, 32, true)), 1024);
+    encryptTestFile($source, Storage::disk('shares')->path($share->token.'/old.enc'), bin2hex(hash_pbkdf2('sha256', 'old-password', hex2bin($salt), 100000, 32, true)), 1024);
     unlink($source);
 
     Livewire::test(ShareDownload::class, ['share' => $share])