Refactor WeChat integration to support multiple mini programs, removing hardcoded WeChat credentials and updating user model and authentication flow accordingly.

internal/service/mini_program_service.go

@@ -0,0 +1,25 @@
+package service
+
+import (
+	"context"
+
+	"wx_service/internal/model"
+
+	"gorm.io/gorm"
+)
+
+type MiniProgramService struct {
+	db *gorm.DB
+}
+
+func NewMiniProgramService(db *gorm.DB) *MiniProgramService {
+	return &MiniProgramService{db: db}
+}
+
+func (s *MiniProgramService) GetByID(ctx context.Context, id uint) (*model.MiniProgram, error) {
+	var mp model.MiniProgram
+	if err := s.db.WithContext(ctx).Where("id = ?", id).First(&mp).Error; err != nil {
+		return nil, err
+	}
+	return &mp, nil
+}