added pgvector implementation and updated doc

backend/build.gradle.kts

@@ -48,6 +48,9 @@ dependencies {
 	implementation("org.springframework.boot:spring-boot-starter-webmvc")
 	implementation("org.springframework.ai:spring-ai-starter-model-openai")
 	implementation("org.postgresql:postgresql:$postgresqlVersion")
+	implementation("org.springframework.ai:spring-ai-starter-vector-store-pgvector")
+
+	
 	
 	compileOnly("org.projectlombok:lombok")
 	

backend/src/main/resources/application.yaml

@@ -21,6 +21,12 @@ spring:
       api-key: ${OPENAI_KEY}
       chat:
         model: gpt-4o-mini
+    vectorstore:
+      pgvector:
+        dimensions: 1536
+        distance-type: COSINE_DISTANCE
+        index-type: HNSW
+        initialize-schema: true
   session:
     store-type: jdbc
     jdbc: