feat(analytics): AVM v2 batch valuation, comparison, history + frontend upgrade

Add batch valuation (POST /analytics/valuation/batch, max 50 properties),
valuation comparison (POST /analytics/valuation/compare, 2-5 properties),
and history endpoint (GET /analytics/valuation/history/:propertyId) with
confidence explanation helper. Frontend: enhanced valuation form with project
autocomplete and deep analysis toggle, results with confidence badges and
price range visualization, comparables table, history chart, market context
card, and PDF export.

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

apps/web/components/valuation/valuation-history-chart.tsx

@@ -0,0 +1,110 @@
+'use client';
+
+import {
+  Area,
+  AreaChart,
+  CartesianGrid,
+  ResponsiveContainer,
+  Tooltip,
+  XAxis,
+  YAxis,
+} from 'recharts';
+import {
+  Card,
+  CardContent,
+  CardDescription,
+  CardHeader,
+  CardTitle,
+} from '@/components/ui/card';
+import { formatPrice } from '@/lib/currency';
+import type { ValuationHistoryPoint } from '@/lib/valuation-api';
+
+interface ValuationHistoryChartProps {
+  data: ValuationHistoryPoint[];
+}
+
+function formatChartDate(dateStr: string): string {
+  const date = new Date(dateStr);
+  return date.toLocaleDateString('vi-VN', { month: 'short', year: '2-digit' });
+}
+
+function formatTooltipDate(dateStr: string): string {
+  const date = new Date(dateStr);
+  return date.toLocaleDateString('vi-VN', {
+    day: '2-digit',
+    month: '2-digit',
+    year: 'numeric',
+  });
+}
+
+export function ValuationHistoryChart({ data }: ValuationHistoryChartProps) {
+  if (data.length < 2) return null;
+
+  const chartData = data.map((point) => ({
+    date: point.date,
+    price: point.estimatedPriceVND,
+    confidence: Math.round(point.confidence * 100),
+  }));
+
+  return (
+    <Card>
+      <CardHeader>
+        <CardTitle className="text-lg">Lịch sử định giá</CardTitle>
+        <CardDescription>
+          Biến động giá ước tính theo thời gian
+        </CardDescription>
+      </CardHeader>
+      <CardContent>
+        <div className="h-64">
+          <ResponsiveContainer width="100%" height="100%">
+            <AreaChart data={chartData} margin={{ top: 5, right: 10, left: 10, bottom: 5 }}>
+              <defs>
+                <linearGradient id="priceGradient" x1="0" y1="0" x2="0" y2="1">
+                  <stop offset="5%" stopColor="hsl(var(--primary))" stopOpacity={0.3} />
+                  <stop offset="95%" stopColor="hsl(var(--primary))" stopOpacity={0} />
+                </linearGradient>
+              </defs>
+              <CartesianGrid strokeDasharray="3 3" className="stroke-muted" />
+              <XAxis
+                dataKey="date"
+                tickFormatter={formatChartDate}
+                className="fill-muted-foreground"
+                fontSize={12}
+              />
+              <YAxis
+                tickFormatter={(val: number) => formatPrice(val)}
+                className="fill-muted-foreground"
+                fontSize={12}
+                width={80}
+              />
+              <Tooltip
+                contentStyle={{
+                  backgroundColor: 'hsl(var(--card))',
+                  border: '1px solid hsl(var(--border))',
+                  borderRadius: '0.5rem',
+                  fontSize: '0.875rem',
+                }}
+                labelFormatter={(label) =>
+                  typeof label === 'string' ? formatTooltipDate(label) : label
+                }
+                formatter={(value, name) => {
+                  const num = Number(value);
+                  if (name === 'price') return [formatPrice(num) + ' VNĐ', 'Giá ước tính'];
+                  if (name === 'confidence') return [`${num}%`, 'Độ tin cậy'];
+                  return [String(value), name];
+                }}
+              />
+              <Area
+                type="monotone"
+                dataKey="price"
+                stroke="hsl(var(--primary))"
+                strokeWidth={2}
+                fill="url(#priceGradient)"
+              />
+            </AreaChart>
+          </ResponsiveContainer>
+        </div>
+      </CardContent>
+    </Card>
+  );
+}