feat: Implement AI response feedback UI and complete high-priority features

Frontend Features:
- Add MessageFeedback component with thumbs up/down buttons
- Positive feedback submits immediately with success toast
- Negative feedback opens dialog for optional text input
- Integrate feedback buttons on all AI assistant messages
- Add success Snackbar confirmation message
- Translation keys added to ai.json (feedback section)

Backend Features:
- Add POST /api/v1/ai/feedback endpoint
- Create FeedbackDto with conversation ID validation
- Implement submitFeedback service method
- Store feedback in conversation metadata with timestamps
- Add audit logging for feedback submissions
- Fix conversationId regex validation to support nanoid format

Legal & Compliance:
- Implement complete EULA acceptance flow with modal
- Create reusable legal content components (Terms, Privacy, EULA)
- Add LegalDocumentViewer for nested modal viewing
- Cookie Consent Banner with GDPR compliance
- Legal pages with AppShell navigation
- EULA acceptance tracking in user entity

Branding Updates:
- Rebrand from "Maternal App" to "ParentFlow"
- Update all icons (72px to 512px) from high-res source
- PWA manifest updated with ParentFlow branding
- Contact email: hello@parentflow.com
- Address: Serbota 3, Bucharest, Romania

Bug Fixes:
- Fix chat endpoint validation (support nanoid conversation IDs)
- Fix EULA acceptance API call (use apiClient vs hardcoded localhost)
- Fix icon loading errors with proper PNG generation

Documentation:
- Mark 11 high-priority features as complete in REMAINING_FEATURES.md
- Update feature statistics: 73/139 complete (53%)
- All high-priority features now complete! 🎉

Files Changed:
Frontend: 21 files (components, pages, locales, icons)
Backend: 6 files (controller, service, DTOs, migrations)
Docs: 1 file (REMAINING_FEATURES.md)

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

maternal-web/components/legal/EULACheck.tsx

@@ -0,0 +1,72 @@
+'use client';
+
+import { useState, useEffect } from 'react';
+import { useAuth } from '@/lib/auth/AuthContext';
+import { EULADialog } from './EULADialog';
+import { useRouter } from 'next/navigation';
+import apiClient from '@/lib/api/client';
+
+export function EULACheck() {
+  const { user, logout } = useAuth();
+  const router = useRouter();
+  const [showDialog, setShowDialog] = useState(false);
+  const [checking, setChecking] = useState(true);
+
+  useEffect(() => {
+    // Only check EULA acceptance for authenticated users
+    if (user) {
+      console.log('🔍 Checking EULA acceptance:', {
+        userId: user.id,
+        eulaAcceptedAt: user.eulaAcceptedAt,
+        eulaVersion: user.eulaVersion,
+      });
+
+      // Show dialog if user hasn't accepted EULA
+      if (!user.eulaAcceptedAt) {
+        console.log('⚠️ User has not accepted EULA, showing dialog');
+        setShowDialog(true);
+      } else {
+        console.log('✅ EULA already accepted on', user.eulaAcceptedAt);
+      }
+    }
+    setChecking(false);
+  }, [user]);
+
+  const handleAccept = async () => {
+    try {
+      console.log('✅ User accepted EULA, calling API...');
+
+      const response = await apiClient.post('/api/v1/auth/eula/accept', {
+        version: '2025-10-04',
+      });
+
+      console.log('✅ EULA acceptance recorded:', response.data);
+
+      // Reload user data to get updated EULA acceptance
+      window.location.reload();
+    } catch (error) {
+      console.error('❌ Failed to accept EULA:', error);
+      alert('Failed to accept EULA. Please try again.');
+    }
+  };
+
+  const handleDecline = async () => {
+    console.log('❌ User declined EULA, logging out...');
+    alert('You must accept the Terms of Service, Privacy Policy, and EULA to use ParentFlow.');
+    await logout();
+    router.push('/login');
+  };
+
+  // Don't render anything while checking or if user hasn't loaded
+  if (checking || !user) {
+    return null;
+  }
+
+  return (
+    <EULADialog
+      open={showDialog}
+      onAccept={handleAccept}
+      onDecline={handleDecline}
+    />
+  );
+}