feat(mcp): add MCP Server Integration — Property Search, Analytics, Valuation

Implement 3 MCP servers in libs/mcp-servers/ using @modelcontextprotocol/sdk:

- Property Search: NL search via Typesense, property comparison, detail lookup
- Market Analytics: market reports, price trends, district comparison
- Valuation: AVM integration with Python AI service, feature extraction, batch valuation

Includes NestJS integration module with SSE transport for in-process hosting.

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

libs/mcp-servers/src/shared/types.ts

@@ -0,0 +1,89 @@
+import type { Client as TypesenseClient } from 'typesense';
+
+export interface PropertySearchDeps {
+  typesenseClient: TypesenseClient;
+  collectionName?: string;
+}
+
+export interface MarketAnalyticsDeps {
+  typesenseClient: TypesenseClient;
+  collectionName?: string;
+}
+
+export interface ValuationDeps {
+  aiServiceBaseUrl: string;
+}
+
+export interface McpServerConfig {
+  name: string;
+  version: string;
+}
+
+export interface PropertyComparisonResult {
+  properties: PropertySummary[];
+  comparison: {
+    priceRange: { min: number; max: number; avg: number };
+    areaRange: { min: number; max: number; avg: number };
+    pricePerM2Range: { min: number; max: number; avg: number };
+  };
+}
+
+export interface PropertySummary {
+  listingId: string;
+  title: string;
+  propertyType: string;
+  transactionType: string;
+  priceVND: number;
+  pricePerM2: number | null;
+  areaM2: number;
+  bedrooms: number | null;
+  bathrooms: number | null;
+  address: string;
+  district: string;
+  city: string;
+}
+
+export interface MarketReport {
+  district: string;
+  city: string;
+  propertyType: string | null;
+  totalListings: number;
+  averagePriceVND: number;
+  medianPriceVND: number;
+  averagePricePerM2: number;
+  averageArea: number;
+  priceDistribution: { range: string; count: number }[];
+}
+
+export interface PriceTrend {
+  district: string;
+  city: string;
+  period: string;
+  dataPoints: { label: string; avgPrice: number; count: number }[];
+}
+
+export interface ValuationEstimate {
+  estimatedPriceVND: number;
+  confidence: number;
+  pricePerM2: number;
+  priceRangeLow: number;
+  priceRangeHigh: number;
+}
+
+export interface FeatureExtractionResult {
+  features: {
+    area: number | null;
+    district: string | null;
+    city: string | null;
+    propertyType: string | null;
+    bedrooms: number | null;
+    bathrooms: number | null;
+    floors: number | null;
+    frontage: number | null;
+    roadWidth: number | null;
+    priceMentioned: number | null;
+    hasLegalPaper: boolean | null;
+  };
+  tokens: string[];
+  entities: { text: string; label: string }[];
+}