refactor: 重构WebSocket服务及相关实体类

重构WebSocket服务名称从WebSocketService改为WebSocketClientService，并实现Serializable接口
添加WebSocket常量定义和消息处理实现
优化实体类equals和hashCode方法
修复控制器路径和日志配置
添加查询服务和任务接口方法

server/src/main/java/com/ecep/contract/EntityService.java

@@ -1,4 +1,68 @@
 package com.ecep.contract;
 
-public class EntityService {
+import com.ecep.contract.ds.MyRepository;
+import com.ecep.contract.model.Contract;
+import com.ecep.contract.util.SpecificationUtils;
+import com.fasterxml.jackson.databind.JsonNode;
+import org.springframework.cache.annotation.Cacheable;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.jpa.domain.Specification;
+import org.springframework.util.StringUtils;
+
+import java.util.List;
+
+public abstract class EntityService<T, ID> {
+
+    protected abstract MyRepository<T, ID> getRepository();
+
+    public abstract T createNewEntity();
+
+
+    public long count() {
+        return getRepository().count();
+    }
+
+    public long count(Specification<T> spec) {
+        return getRepository().count(spec);
+    }
+
+    public long count(JsonNode paramsNode) {
+        return getRepository().count(buildParameterSpecification(paramsNode));
+    }
+
+    protected abstract Specification<T> buildParameterSpecification(JsonNode paramsNode);
+
+    public Page<T> findAll(JsonNode paramsNode, Pageable pageable) {
+        Specification<T> spec = null;
+        if (paramsNode.has("searchText")) {
+            spec = getSpecification(paramsNode.get("searchText").asText());
+        }
+        spec = SpecificationUtils.and(spec, buildParameterSpecification(paramsNode));
+        return findAll(spec, pageable);
+    }
+
+
+    public Page<T> findAll(Specification<T> spec, Pageable pageable) {
+        return getRepository().findAll(spec, pageable);
+    }
+
+    public List<T> findAll(Specification<T> spec, Sort sort) {
+        return getRepository().findAll(spec, sort);
+    }
+
+    protected abstract Specification<T> buildSearchSpecification(String searchText);
+
+    public Specification<T> getSpecification(String searchText) {
+        if (!StringUtils.hasText(searchText)) {
+            return null;
+        }
+        return SpecificationUtils.andWith(searchText, this::buildSearchSpecification);
+    }
+
+    public List<T> search(String searchText) {
+        Specification<T> spec = getSpecification(searchText);
+        return getRepository().findAll(spec, Pageable.ofSize(10)).getContent();
+    }
 }