chore: 全面规范化代码，遵循 CLAUDE.md 编码规范

- C# 文件命名改为 snake_case（28 个文件重命名）
- C# 类转换为主构造函数（8 个类）
- 空 catch 添加异常类型（2 处）
- 新建 GlobalUsings.cs（Health.Infrastructure、Health.WebApi）
- Flutter 移除 go_router，改用 Riverpod 路由栈
- Flutter 移除 flutter_secure_storage，改用 sqflite 持久化
- 修复 Flutter 构建路径（Flutter SDK 迁至 D 盘）
- 后端端口改为 0.0.0.0:5000，支持局域网访问

backend/src/Health.Domain/Entities/support_entities.cs

@@ -0,0 +1,99 @@
+using Health.Domain.Enums;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace Health.Domain.Entities;
+
+/// <summary>
+/// 复查/随访计划
+/// </summary>
+public sealed class FollowUp
+{
+    public Guid Id { get; set; }
+    public Guid UserId { get; set; }
+    public string Title { get; set; } = string.Empty;
+    public string? DoctorName { get; set; }
+    public string? Department { get; set; }
+    public DateTime ScheduledAt { get; set; }
+    public string? Notes { get; set; }
+    public FollowUpStatus Status { get; set; }
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+    public User User { get; set; } = null!;
+}
+
+/// <summary>
+/// 健康档案
+/// </summary>
+public sealed class HealthArchive
+{
+    public Guid Id { get; set; }
+    public Guid UserId { get; set; }
+    public string? Diagnosis { get; set; }          // 主要诊断
+    public string? SurgeryType { get; set; }        // 手术类型
+    public DateOnly? SurgeryDate { get; set; }      // 手术日期
+    public List<string> Allergies { get; set; } = [];           // 过敏信息
+    public List<string> DietRestrictions { get; set; } = [];    // 饮食限制
+    public List<string> ChronicDiseases { get; set; } = [];     // 慢病史
+    public string? FamilyHistory { get; set; }       // 家族病史
+    public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
+
+    public User User { get; set; } = null!;
+}
+
+/// <summary>
+/// 刷新令牌
+/// </summary>
+public sealed class RefreshToken
+{
+    public Guid Id { get; set; }
+    public Guid UserId { get; set; }
+    public string Token { get; set; } = string.Empty;
+    public DateTime ExpiresAt { get; set; }
+    public bool IsRevoked { get; set; }
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+}
+
+/// <summary>
+/// 短信验证码
+/// </summary>
+public sealed class VerificationCode
+{
+    public Guid Id { get; set; }
+    public string Phone { get; set; } = string.Empty;
+    public string Code { get; set; } = string.Empty;
+    public DateTime ExpiresAt { get; set; }
+    public bool IsUsed { get; set; }
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+}
+
+/// <summary>
+/// 通知偏好
+/// </summary>
+public sealed class NotificationPreference
+{
+    public Guid Id { get; set; }
+    public Guid UserId { get; set; }
+    public bool MedicationReminder { get; set; } = true;
+    public bool FollowUpReminder { get; set; } = true;
+    public bool DoctorReply { get; set; } = true;
+    public bool AbnormalAlert { get; set; } = true;
+    public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
+
+    public User User { get; set; } = null!;
+}
+
+/// <summary>
+/// 设备推送 token
+/// </summary>
+public sealed class DeviceToken
+{
+    public Guid Id { get; set; }
+    public Guid UserId { get; set; }
+    public string Platform { get; set; } = string.Empty; // ios / android
+    public string PushToken { get; set; } = string.Empty;
+    public bool IsActive { get; set; } = true;
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+    public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
+
+    public User User { get; set; } = null!;
+}