feat(web): add Property Valuation UI with AVM integration

Build the valuation page at /dashboard/valuation with form input,
AI-powered price estimation results, comparable properties display,
and valuation history. Add "Dinh gia AI" button to listing detail
sidebar for quick per-listing estimates.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/app/(public)/listings/[id]/page.tsx

@@ -8,6 +8,7 @@ import { ImageGallery } from '@/components/listings/image-gallery';
 import { Badge } from '@/components/ui/badge';
 import { Button } from '@/components/ui/button';
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { AiEstimateButton } from '@/components/valuation/ai-estimate-button';
 import { listingsApi, type ListingDetail } from '@/lib/listings-api';
 import { PROPERTY_TYPES, DIRECTIONS, TRANSACTION_TYPES } from '@/lib/validations/listings';
 
@@ -264,6 +265,9 @@ export default function PublicListingDetailPage() {
             </CardContent>
           </Card>
 
+          {/* AI Estimate */}
+          <AiEstimateButton listingId={listing.id} />
+
           {/* Stats */}
           <Card>
             <CardContent className="pt-6">