feat: Apple-style donation-focused landing page + Azure OpenAI fixes

Major updates:
- Replace homepage with clean, minimalist Apple-style landing page
- Focus on donation messaging and mission statement
- Add comprehensive AI chat analysis documentation
- Fix Azure OpenAI configuration with correct endpoints
- Update embedding API to use text-embedding-ada-002 (1536 dims)

Landing Page Features:
- Hero section with tagline "Every Scripture. Every Language. Forever Free"
- Mission statement emphasizing free access
- Matthew 10:8 verse highlight
- 6 feature cards (Global Library, Multilingual, Prayer Wall, AI Chat, Privacy, Offline)
- Donation CTA sections with PayPal and card options
- "Why It Matters" section with dark background
- Clean footer with navigation links

Technical Changes:
- Updated .env.local with new Azure credentials
- Fixed vector-search.ts to support separate embed API version
- Integrated AuthModal into Bible reader and prayers page
- Made prayer filters collapsible and mobile-responsive
- Changed language picker to single-select

Documentation Created:
- AI_CHAT_FIX_PLAN.md - Comprehensive implementation plan
- AI_CHAT_VERIFICATION_FINDINGS.md - Database analysis
- AI_CHAT_ANALYSIS_SUMMARY.md - Executive summary
- AI_CHAT_STATUS_UPDATE.md - Current status and next steps
- logo.svg - App logo (MenuBook icon)

Build: ✅ Successful (Next.js 15.5.3)

🤖 Generated with Claude Code

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

messages/it.json

@@ -269,6 +269,8 @@
     "prayers": {
       "title": "Preghiere",
       "subtitle": "Condividi preghiere e prega insieme alla comunità",
+      "addPrayer": "Aggiungi preghiera",
+      "authRequired": "Effettua l'accesso per aggiungere una preghiera e unirti alla nostra comunità di preghiera.",
       "viewModes": {
         "private": "Le mie preghiere private",
         "public": "Muro delle preghiere pubblico"
@@ -279,7 +281,7 @@
       },
       "languageFilter": {
         "title": "Lingue",
-        "helper": "Scegli quali lingue includere. La tua lingua corrente rimane selezionata.",
+        "helper": "Vedi preghiere in altre lingue",
         "options": {
           "en": "Inglese",
           "ro": "Rumeno",