feat(login): 添加记住我登录功能

前端新增记住我勾选框，登录页挂载时自动恢复已保存的用户名，勾选时将用户名存入本地存储并在登录请求中携带对应参数；后端新增rememberMe参数处理逻辑，配置7天免登录的JWT有效期，重载JWT工具类以支持自定义令牌过期时间

backend/src/main/java/com/bycrm/dto/LoginDTO.java

@@ -24,4 +24,9 @@ public class LoginDTO implements Serializable {
      */
     @NotBlank(message = "密码不能为空")
     private String password;
+
+    /**
+     * 记住我（true 时签发 7 天有效期的 token）
+     */
+    private Boolean rememberMe = false;
 }

backend/src/main/java/com/bycrm/service/impl/UserServiceImpl.java

@@ -46,6 +46,10 @@ public class UserServiceImpl implements UserService {
             throw new BusinessException("用户名或密码错误");
         }
 
+        if (Boolean.TRUE.equals(loginDTO.getRememberMe())) {
+            return jwtUtil.generateToken(user.getId(), user.getUsername(), user.getRole(),
+                    user.getDealerId(), jwtUtil.getRememberExpiration());
+        }
         return jwtUtil.generateToken(user.getId(), user.getUsername(), user.getRole(), user.getDealerId());
     }
 

backend/src/main/java/com/bycrm/util/JwtUtil.java

@@ -25,24 +25,45 @@ public class JwtUtil {
     @Value("${jwt.expiration}")
     private Long expiration;
 
+    @Value("${jwt.remember-expiration:604800000}")
+    private Long rememberExpiration;
+
+    public Long getRememberExpiration() {
+        return rememberExpiration;
+    }
+
     /**
      * 生成 Token
      */
     public String generateToken(Long userId, String username, Integer role, Long dealerId) {
+        return generateToken(userId, username, role, dealerId, expiration);
+    }
+
+    /**
+     * 生成指定有效期的 Token（用于"记住我"延长有效期）
+     */
+    public String generateToken(Long userId, String username, Integer role, Long dealerId, long expirationMillis) {
         Map<String, Object> claims = new HashMap<>();
         claims.put("userId", userId);
         claims.put("username", username);
         claims.put("role", role);
         claims.put("dealerId", dealerId);
-        return generateToken(claims);
+        return generateToken(claims, expirationMillis);
     }
 
     /**
      * 生成 Token
      */
     public String generateToken(Map<String, Object> claims) {
+        return generateToken(claims, expiration);
+    }
+
+    /**
+     * 生成指定有效期的 Token
+     */
+    public String generateToken(Map<String, Object> claims, long expirationMillis) {
         Date now = new Date();
-        Date expiryDate = new Date(now.getTime() + expiration);
+        Date expiryDate = new Date(now.getTime() + expirationMillis);
 
         return Jwts.builder()
                 .setClaims(claims)

backend/src/main/resources/application.yml

@@ -58,6 +58,7 @@ jwt:
   # 生产环境请使用环境变量或密钥管理系统存储此密钥
   secret: by-crm-jwt-secret-key-2024-hs512-requires-at-least-64-bytes-for-secure-signing-please-change-in-production-environment
   expiration: 86400000  # 24小时，单位：毫秒
+  remember-expiration: 604800000  # 记住我：7天免登录，单位：毫秒
 
 # CRM 业务配置
 crm: