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>

Dockerfile

@@ -48,6 +48,9 @@ RUN install-php-extensions \
     pcntl \
     zip
 
+# PHP limits, read from PHP_* environment variables by PHP itself
+COPY docker/php/uploads.ini /usr/local/etc/php/conf.d/99-uploads.ini
+
 WORKDIR /app
 
 # ============================================
@@ -56,8 +59,9 @@ WORKDIR /app
 # Holds only the tools: the checkout is mounted at /app, and its entrypoint runs from there.
 FROM base AS dev
 
-# For the dev packages: Pest's browser plugin needs sockets
-RUN install-php-extensions sockets
+# For the dev packages: Pest's browser plugin needs sockets; the screenshot publisher and fake test
+# images need gd (the app itself never processes images, so production goes without)
+RUN install-php-extensions sockets gd
 
 # Node.js for the Vite dev server
 RUN apk add --no-cache nodejs npm
@@ -93,9 +97,6 @@ ENV APP_NAME="SealShare" \
     BCRYPT_ROUNDS="12" \
     OCTANE_SERVER="frankenphp"
 
-# Copy PHP ini for upload limits
-COPY docker/php/uploads.ini /usr/local/etc/php/conf.d/99-uploads.ini
-
 # Copy application code
 COPY . .