add frontend application structure with authentication, generation features, and integration tests

frontend/app/templates/dashboard.html

@@ -0,0 +1,9 @@
+{% extends "base.html" %}
+{% block title %}Dashboard — AI Allucanget{% endblock %}
+{% block content %}
+<div class="card">
+  <h1>Welcome{% if user.get('email') %}, {{ user.email }}{% endif %}</h1>
+  <p>Role: <strong>{{ user.get('role', 'user') }}</strong></p>
+  <a href="{{ url_for('generate') }}" class="btn">Start generating</a>
+</div>
+{% endblock %}