site-builder: surface Spotify/Twitch + contact-form recipient in the Styles (guided) panel

The right panel only renders GuidedStyles (there is no Settings tab), so the
per-component Settings panels I'd edited never showed. Add Spotify/Twitch to
SocialStylePanel's platform dropdown and the 'Send submissions to' + thank-you
fields to FormStylePanel (shown for any form with a recipientEmail prop).

craft/src/panels/right/styles/SocialStylePanel.tsx

@@ -83,7 +83,7 @@ export const SocialStylePanel: React.FC<StylePanelProps> = ({ selectedId, nodePr
               style={{ width: '100%', padding: '6px', fontSize: 11, background: '#27272a', color: '#e4e4e7', border: '1px solid #3f3f46', borderRadius: 4, cursor: 'pointer' }}
             >
               <option value="">+ Add Platform...</option>
-              {['facebook', 'twitter', 'instagram', 'linkedin', 'youtube', 'github', 'tiktok', 'pinterest', 'snapchat', 'whatsapp'].map((p) => (
+              {['facebook', 'twitter', 'instagram', 'linkedin', 'youtube', 'github', 'tiktok', 'pinterest', 'snapchat', 'whatsapp', 'spotify', 'twitch'].map((p) => (
                 <option key={p} value={p}>{p.charAt(0).toUpperCase() + p.slice(1)}</option>
               ))}
             </select>