Implement a mobile-friendly navigation system that replaces the static nav menu with a hamburger toggle button on screens ≤768px. The menu slides in from the left as a fixed overlay panel with smooth CSS transitions, and automatically closes when any nav link is clicked. Includes animated hamburger icon transformation (rotating top/bottom bars, hiding middle bar) and adjusted hero section padding for better mobile layout.
- Update `generate_legal_documents` default `template_dir` from `"templates/legal"` to `"mywebdav/templates/legal"`
- Update `Jinja2Templates` directory from `"templates"` to `"mywebdav/templates"`
- Add new `base.html` template with navigation, footer, and SEO meta tags
- Add new `features.html` template with responsive grid layout and feature cards
- Add new legal document templates: `compliance_statement.html`, `contact_complaint_mechanism.html`, `cookie_policy.html`, `data_portability_deletion_policy.html`
