feat(search): implement Search module with Typesense full-text & geo search

- TypesenseClient service with configurable connection
- Collection schema for listings with facets, geo-point, and Vietnamese text
- ListingIndexer service with PostGIS coordinate extraction for geo search
- CQRS commands: SyncListing, ReindexAll (batch with pagination)
- CQRS queries: SearchProperties (filters, sorting), GeoSearch (radius)
- Event handlers for listing.approved/updated/deactivated auto-sync
- REST endpoints: GET /search, GET /search/geo, POST /search/reindex (admin)
- DTOs with class-validator validation and pagination

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

apps/api/src/modules/search/application/queries/geo-search/geo-search.handler.ts

@@ -0,0 +1,43 @@
+import { type IQueryHandler, QueryHandler } from '@nestjs/cqrs';
+import { Inject } from '@nestjs/common';
+import { GeoSearchQuery } from './geo-search.query';
+import {
+  SEARCH_REPOSITORY,
+  type ISearchRepository,
+  type SearchResult,
+} from '../../../domain/repositories/search.repository';
+
+@QueryHandler(GeoSearchQuery)
+export class GeoSearchHandler implements IQueryHandler<GeoSearchQuery> {
+  constructor(
+    @Inject(SEARCH_REPOSITORY) private readonly searchRepo: ISearchRepository,
+  ) {}
+
+  async execute(query: GeoSearchQuery): Promise<SearchResult> {
+    const filters: string[] = ['status:=ACTIVE'];
+
+    if (query.propertyType) {
+      filters.push(`propertyType:=${query.propertyType}`);
+    }
+    if (query.transactionType) {
+      filters.push(`transactionType:=${query.transactionType}`);
+    }
+    if (query.priceMin !== undefined && query.priceMax !== undefined) {
+      filters.push(`priceVND:[${query.priceMin}..${query.priceMax}]`);
+    } else if (query.priceMin !== undefined) {
+      filters.push(`priceVND:>=${query.priceMin}`);
+    } else if (query.priceMax !== undefined) {
+      filters.push(`priceVND:<=${query.priceMax}`);
+    }
+
+    return this.searchRepo.search({
+      query: '*',
+      filterBy: filters.join(' && '),
+      sortBy: query.sortBy,
+      page: query.page,
+      perPage: query.perPage,
+      geoPoint: { lat: query.lat, lng: query.lng },
+      geoRadiusKm: Math.min(query.radiusKm, 100),
+    });
+  }
+}

apps/api/src/modules/search/application/queries/geo-search/geo-search.query.ts

@@ -0,0 +1,14 @@
+export class GeoSearchQuery {
+  constructor(
+    public readonly lat: number,
+    public readonly lng: number,
+    public readonly radiusKm: number,
+    public readonly propertyType?: string,
+    public readonly transactionType?: string,
+    public readonly priceMin?: number,
+    public readonly priceMax?: number,
+    public readonly sortBy?: string,
+    public readonly page?: number,
+    public readonly perPage?: number,
+  ) {}
+}

apps/api/src/modules/search/application/queries/search-properties/search-properties.handler.ts

@@ -0,0 +1,57 @@
+import { type IQueryHandler, QueryHandler } from '@nestjs/cqrs';
+import { Inject } from '@nestjs/common';
+import { SearchPropertiesQuery } from './search-properties.query';
+import {
+  SEARCH_REPOSITORY,
+  type ISearchRepository,
+  type SearchResult,
+} from '../../../domain/repositories/search.repository';
+
+@QueryHandler(SearchPropertiesQuery)
+export class SearchPropertiesHandler implements IQueryHandler<SearchPropertiesQuery> {
+  constructor(
+    @Inject(SEARCH_REPOSITORY) private readonly searchRepo: ISearchRepository,
+  ) {}
+
+  async execute(query: SearchPropertiesQuery): Promise<SearchResult> {
+    const filters: string[] = ['status:=ACTIVE'];
+
+    if (query.propertyType) {
+      filters.push(`propertyType:=${query.propertyType}`);
+    }
+    if (query.transactionType) {
+      filters.push(`transactionType:=${query.transactionType}`);
+    }
+    if (query.priceMin !== undefined && query.priceMax !== undefined) {
+      filters.push(`priceVND:[${query.priceMin}..${query.priceMax}]`);
+    } else if (query.priceMin !== undefined) {
+      filters.push(`priceVND:>=${query.priceMin}`);
+    } else if (query.priceMax !== undefined) {
+      filters.push(`priceVND:<=${query.priceMax}`);
+    }
+    if (query.areaMin !== undefined && query.areaMax !== undefined) {
+      filters.push(`areaM2:[${query.areaMin}..${query.areaMax}]`);
+    } else if (query.areaMin !== undefined) {
+      filters.push(`areaM2:>=${query.areaMin}`);
+    } else if (query.areaMax !== undefined) {
+      filters.push(`areaM2:<=${query.areaMax}`);
+    }
+    if (query.bedrooms !== undefined) {
+      filters.push(`bedrooms:>=${query.bedrooms}`);
+    }
+    if (query.district) {
+      filters.push(`district:=${query.district}`);
+    }
+    if (query.city) {
+      filters.push(`city:=${query.city}`);
+    }
+
+    return this.searchRepo.search({
+      query: query.query,
+      filterBy: filters.join(' && '),
+      sortBy: query.sortBy,
+      page: query.page,
+      perPage: query.perPage,
+    });
+  }
+}

apps/api/src/modules/search/application/queries/search-properties/search-properties.query.ts

@@ -0,0 +1,17 @@
+export class SearchPropertiesQuery {
+  constructor(
+    public readonly query?: string,
+    public readonly propertyType?: string,
+    public readonly transactionType?: string,
+    public readonly priceMin?: number,
+    public readonly priceMax?: number,
+    public readonly areaMin?: number,
+    public readonly areaMax?: number,
+    public readonly bedrooms?: number,
+    public readonly district?: string,
+    public readonly city?: string,
+    public readonly sortBy?: string,
+    public readonly page?: number,
+    public readonly perPage?: number,
+  ) {}
+}