Add FAQ Section to Lovable App

Add an FAQ section to my Lovable app with FAQPage schema markup.

REQUIREMENTS:
1. Create a reusable FAQ accordion component that shows question text with a toggle icon. Clicking expands to reveal the answer with a smooth animation.
2. Only one FAQ can be open at a time (accordion behavior). Clicking an open FAQ closes it.
3. Add FAQPage structured data (JSON-LD) in the page head. Each question/answer pair must be included for Google rich results.
4. Store FAQ content in a Supabase "faqs" table so they can be managed without code changes.
5. Support categories to group FAQs (e.g., "Pricing", "Features", "Getting Started") with tab navigation.
6. Add a search/filter input above the FAQs that filters questions as the user types.
7. Mobile-responsive with full-width accordions and adequate tap targets.

DATABASE:
- "faqs" table: id, question, answer, category, sort_order, is_published, created_at
- RLS: Anyone can read published FAQs. Only admins can create/edit.

SECURITY:
- Sanitize FAQ content to prevent XSS if answers contain HTML.