refactor: 清理代码、优化结构

- 移除订阅消息相关代码(WxSubscribeMessageService、subscribeTemplateId配置)
- 提取Result类为独立公共类(common.Result)
- 拆分Controller: WxLoginController(登录) + AppointmentController(预约)
- 引入Lombok(@Data/@Slf4j/@RequiredArgsConstructor)消除样板代码
- 修正WxLoginResult字段命名(session_key->sessionKey+@JsonProperty)
- MySQL驱动升级mysql-connector-java->mysql-connector-j
- updateStatus SQL增加status='pending'校验防并发重复审批
- pom.xml配置spring-boot-maven-plugin排除lombok

src/main/java/com/example/mini_program/entity/VisitApplication.java

@@ -1,5 +1,9 @@
 package com.example.mini_program.entity;
 
+import com.fasterxml.jackson.annotation.JsonAlias;
+import lombok.Data;
+
+@Data
 public class VisitApplication {
 
     private String id;
@@ -7,116 +11,17 @@ public class VisitApplication {
     private String phone;
     private String company;
     private String reason;
+
+    @JsonAlias("date")
     private String visitDate;
+
+    @JsonAlias("time")
     private String visitTime;
+
     private String hostName;
     private String area;
     private String status;
     private String statusText;
     private String openid;
     private String createTime;
-
-    public String getId() {
-        return id;
-    }
-
-    public void setId(String id) {
-        this.id = id;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public void setName(String name) {
-        this.name = name;
-    }
-
-    public String getPhone() {
-        return phone;
-    }
-
-    public void setPhone(String phone) {
-        this.phone = phone;
-    }
-
-    public String getCompany() {
-        return company;
-    }
-
-    public void setCompany(String company) {
-        this.company = company;
-    }
-
-    public String getReason() {
-        return reason;
-    }
-
-    public void setReason(String reason) {
-        this.reason = reason;
-    }
-
-    public String getVisitDate() {
-        return visitDate;
-    }
-
-    public void setVisitDate(String visitDate) {
-        this.visitDate = visitDate;
-    }
-
-    public String getVisitTime() {
-        return visitTime;
-    }
-
-    public void setVisitTime(String visitTime) {
-        this.visitTime = visitTime;
-    }
-
-    public String getHostName() {
-        return hostName;
-    }
-
-    public void setHostName(String hostName) {
-        this.hostName = hostName;
-    }
-
-    public String getArea() {
-        return area;
-    }
-
-    public void setArea(String area) {
-        this.area = area;
-    }
-
-    public String getStatus() {
-        return status;
-    }
-
-    public void setStatus(String status) {
-        this.status = status;
-    }
-
-    public String getStatusText() {
-        return statusText;
-    }
-
-    public void setStatusText(String statusText) {
-        this.statusText = statusText;
-    }
-
-    public String getOpenid() {
-        return openid;
-    }
-
-    public void setOpenid(String openid) {
-        this.openid = openid;
-    }
-
-    public String getCreateTime() {
-        return createTime;
-    }
-
-    public void setCreateTime(String createTime) {
-        this.createTime = createTime;
-    }
 }