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>

components/chat/floating-chat.tsx

@@ -45,6 +45,7 @@ import {
 import { useState, useRef, useEffect, useCallback } from 'react'
 import { useTranslations, useLocale } from 'next-intl'
 import ReactMarkdown from 'react-markdown'
+import { AuthModal } from '@/components/auth/auth-modal'
 
 interface ChatMessage {
   id: string
@@ -95,6 +96,7 @@ export default function FloatingChat() {
   const [showRenameDialog, setShowRenameDialog] = useState(false)
   const [showDeleteDialog, setShowDeleteDialog] = useState(false)
   const [newTitle, setNewTitle] = useState('')
+  const [authModalOpen, setAuthModalOpen] = useState(false)
   const messagesEndRef = useRef<HTMLDivElement>(null)
 
   const scrollToBottom = () => {
@@ -123,6 +125,15 @@ export default function FloatingChat() {
     return () => window.removeEventListener('floating-chat:open', handler as EventListener)
   }, [])
 
+  // Listen for auth sign-in required events
+  useEffect(() => {
+    const handler = () => {
+      setAuthModalOpen(true)
+    }
+    window.addEventListener('auth:sign-in-required', handler as EventListener)
+    return () => window.removeEventListener('auth:sign-in-required', handler as EventListener)
+  }, [])
+
   // Check authentication status
   useEffect(() => {
     checkAuthStatus()
@@ -429,6 +440,12 @@ export default function FloatingChat() {
 
   const toggleFullscreen = () => setIsFullscreen(prev => !prev)
 
+  const handleAuthSuccess = () => {
+    setAuthModalOpen(false)
+    // Re-check auth status to update the UI
+    checkAuthStatus()
+  }
+
   return (
     <>
       {/* Floating Action Button */}
@@ -999,6 +1016,17 @@ export default function FloatingChat() {
           )}
         </Paper>
       </Slide>
+
+      {/* Auth Modal */}
+      <AuthModal
+        open={authModalOpen}
+        onClose={() => setAuthModalOpen(false)}
+        onSuccess={handleAuthSuccess}
+        message={locale === 'ro'
+          ? 'Vă rugăm să vă autentificați pentru a accesa chat-ul AI și a salva conversațiile.'
+          : 'Please sign in to access the AI chat and save your conversations.'}
+        defaultTab="login"
+      />
     </>
   )
 }