Add testimonials section and Q&A submit CTA; v1.0.8

- Testimonials: new Testimonial type, CMS field, admin UI under About,
  and TestimonialsSection rendered on homepage and About page (hidden when empty)
- Q&A: "Submit a Question →" CTA at bottom of Q&A page linking to /contact

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/QASection.tsx

@@ -1,4 +1,5 @@
 import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
+import { Link } from 'react-router-dom'
 
 interface PublicQuestion {
   id: string
@@ -1009,6 +1010,10 @@ export default function QASection() {
             )}
           </>
         )}
+        <div className="qa-submit-cta">
+          <p className="qa-submit-cta-text">Have a question about Scripture or the podcast?</p>
+          <Link to="/contact" className="btn-primary">Submit a Question →</Link>
+        </div>
       </div>
     </section>
   )