Refactor configuration and security features for improved development experience

- Updated the .env.example file to reflect a development environment setup with enhanced secret key requirements and local host settings.
- Modified the Docker Compose configuration to enhance security with read-only settings and no-new-privileges options.
- Updated requirements.txt to pin package versions for better dependency management.
- Enhanced the FastAPI application to include dynamic OpenAPI and documentation URLs based on the environment.
- Implemented session versioning in JWT tokens to improve security and user session management.
- Added new validation for user roles and password strength in schemas.
- Improved email sending logic to handle recipient lists more robustly and added logging for SMTP operations.
- Updated dashboard and profile templates to reflect new features and improve user experience.

app/templates/profile.html

@@ -48,7 +48,7 @@
                 </label>
                 <div class="form-row">
                     <label>Neues Passwort
-                        <input type="password" name="new_password" required minlength="10" autocomplete="new-password" placeholder="Mindestens 10 Zeichen">
+                        <input type="password" name="new_password" required minlength="10" autocomplete="new-password" placeholder="Mind. 10 Zeichen, Groß/Klein/Ziffer">
                     </label>
                     <label>Neues Passwort bestätigen
                         <input type="password" name="confirm_password" required minlength="10" autocomplete="new-password">