为 9 个模块添加 Context 超时控制

完成模块：
- auth: 3 个 Repository 方法 + Service + Handler + Middleware
- wallet: 已有 context 支持，修复依赖调用
- payment: 已有 context 支持，修复 wallet 调用
- adminaudit: 1 个方法
- notification: 2 个方法
- realname: 2 个方法
- systemconfig: 4 个方法
- adminauth: 7 个方法
- adminuser: 6 个方法

所有数据库调用已改为 r.db.WithContext(ctx)，完整传递 context 链路。

待完成模块: order, listing, chat 等 12 个模块（约 157 个方法）

backend/internal/modules/notification/handler.go

@@ -40,7 +40,7 @@ func (h *Handler) List(c *gin.Context) {
 		return
 	}
 	page, pageSize := parsePagination(c)
-	result, err := h.service.List(userID, page, pageSize)
+	result, err := h.service.List(c.Request.Context(), userID, page, pageSize)
 	if err != nil {
 		writeNotificationError(c, err)
 		return
@@ -59,7 +59,7 @@ func (h *Handler) MarkRead(c *gin.Context) {
 		response.BadRequest(c, "ID 不正确")
 		return
 	}
-	if err := h.service.MarkRead(userID, id); err != nil {
+	if err := h.service.MarkRead(c.Request.Context(), userID, id); err != nil {
 		writeNotificationError(c, err)
 		return
 	}

backend/internal/modules/notification/repository.go

@@ -1,6 +1,7 @@
 package notification
 
 import (
+	"context"
 	"time"
 
 	"hfb_sys/backend/internal/model"
@@ -25,14 +26,14 @@ func NewRepository(db *gorm.DB) *Repository {
 	return &Repository{db: db}
 }
 
-func (r *Repository) List(userID uint64, page, pageSize int) (*PaginatedResult, error) {
+func (r *Repository) List(ctx context.Context, userID uint64, page, pageSize int) (*PaginatedResult, error) {
 	var total int64
-	if err := r.db.Model(&model.Notification{}).Where("user_id = ?", userID).Count(&total).Error; err != nil {
+	if err := r.db.WithContext(ctx).Model(&model.Notification{}).Where("user_id = ?", userID).Count(&total).Error; err != nil {
 		return nil, err
 	}
 	offset := (page - 1) * pageSize
 	var rows []model.Notification
-	if err := r.db.Where("user_id = ?", userID).Order("id DESC").Offset(offset).Limit(pageSize).Find(&rows).Error; err != nil {
+	if err := r.db.WithContext(ctx).Where("user_id = ?", userID).Order("id DESC").Offset(offset).Limit(pageSize).Find(&rows).Error; err != nil {
 		return nil, err
 	}
 	items := make([]NotificationDTO, 0, len(rows))
@@ -42,9 +43,9 @@ func (r *Repository) List(userID uint64, page, pageSize int) (*PaginatedResult,
 	return &PaginatedResult{Items: items, Total: total, Page: page, PageSize: pageSize}, nil
 }
 
-func (r *Repository) MarkRead(userID uint64, id uint64) error {
+func (r *Repository) MarkRead(ctx context.Context, userID uint64, id uint64) error {
 	now := time.Now()
-	return r.db.Model(&model.Notification{}).
+	return r.db.WithContext(ctx).Model(&model.Notification{}).
 		Where("id = ? AND user_id = ?", id, userID).
 		Update("read_at", now).Error
 }

backend/internal/modules/notification/service.go

@@ -1,6 +1,9 @@
 package notification
 
-import "errors"
+import (
+	"context"
+	"errors"
+)
 
 var ErrDependencyUnavailable = errors.New("dependency unavailable")
 
@@ -12,16 +15,16 @@ func NewService(repo *Repository) *Service {
 	return &Service{repo: repo}
 }
 
-func (s *Service) List(userID uint64, page, pageSize int) (*PaginatedResult, error) {
+func (s *Service) List(ctx context.Context, userID uint64, page, pageSize int) (*PaginatedResult, error) {
 	if s.repo == nil {
 		return nil, ErrDependencyUnavailable
 	}
-	return s.repo.List(userID, page, pageSize)
+	return s.repo.List(ctx, userID, page, pageSize)
 }
 
-func (s *Service) MarkRead(userID uint64, id uint64) error {
+func (s *Service) MarkRead(ctx context.Context, userID uint64, id uint64) error {
 	if s.repo == nil {
 		return ErrDependencyUnavailable
 	}
-	return s.repo.MarkRead(userID, id)
+	return s.repo.MarkRead(ctx, userID, id)
 }