feat: add hobbies + dietPreferences to User entity + UpdateUserDTO

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

cfc-backend/src/main/java/com/etotem/cfc/dto/UpdateUserDTO.java

@@ -27,6 +27,9 @@ public class UpdateUserDTO {
     // 家长身份
     private String familyRole;
 
+    private String hobbies;
+    private String dietPreferences;
+
     // AI助手形象: xibao(浠宝)/fubao(福宝)
     private String mascot;
 }

cfc-backend/src/main/java/com/etotem/cfc/entity/User.java

@@ -75,6 +75,8 @@ public class User implements Serializable {
     private String bloodType; // 血型
     private String highestEducation; // 最高学历
     private String maritalStatus; // 婚姻状态
+    private String hobbies; // 兴趣爱好
+    private String dietPreferences; // 饮食偏好
 
     // 家长身份: 爸爸/妈妈/爷爷/奶奶/姥爷/姥姥/其他
     private String familyRole;