Add blueprints for authentication, admin, dashboard, gallery, generation, and profile routes

- Created `__init__.py` for blueprint registration.
- Implemented `auth.py` for user authentication (login, register, logout).
- Added `admin.py` for admin functionalities (user management, stats).
- Developed `dashboard.py` for user dashboard displaying user info and generated content.
- Created `gallery.py` for managing and displaying images and videos.
- Implemented `generate.py` for text, image, and video generation functionalities.
- Added `profile.py` for user profile management.
- Updated templates to reflect new route structures and improve navigation.

frontend/app/routes/__init__.py

@@ -0,0 +1,19 @@
+"""Blueprint registration."""
+from flask import Flask
+
+
+def register_blueprints(app: Flask):
+    """Register all application blueprints."""
+    from .auth import auth_bp
+    from .dashboard import dashboard_bp
+    from .gallery import gallery_bp
+    from .generate import generate_bp
+    from .admin import admin_bp
+    from .profile import profile_bp
+
+    app.register_blueprint(auth_bp)
+    app.register_blueprint(dashboard_bp)
+    app.register_blueprint(gallery_bp)
+    app.register_blueprint(generate_bp)
+    app.register_blueprint(admin_bp)
+    app.register_blueprint(profile_bp)