refactor(server): decouple services and improve architecture

- Introduce interfaces for all major services (JWT, PostAI, Comment, Message, Notification, QRCodeLogin, Upload, Vote, etc.) to support dependency inversion.
- Move query parameters from `internal/dto` to a new `internal/query` package to separate request payloads from data transfer objects.
- Refactor `internal/router` to use embedded `RouterDeps` for cleaner dependency management.
- Decouple handlers from repositories by injecting services instead of direct repository access, ensuring proper layering.
- Improve database initialization by moving it from `internal/model` to `internal/database`.
- Optimize message decryption by implementing a more efficient `BatchDecrypt` method in `MessageEncryptor` using a worker pool.
- Enhance error handling and security by implementing fail-fast checks for encryption key length during startup.
- Clean up unused code, including the `avatar` package and several unused DTOs.

internal/service/empty_classroom_sync_service.go

@@ -15,12 +15,12 @@ import (
 )
 
 type SyncEmptyClassroomsRequest struct {
-	Username    string `json:"username" binding:"required"`
-	Password    string `json:"password" binding:"required"`
-	Semester    string `json:"semester"`
-	WeekStart   string `json:"week_start"`
-	WeekEnd     string `json:"week_end"`
-	CampusCode  string `json:"campus_code"`
+	Username   string `json:"username" binding:"required"`
+	Password   string `json:"password" binding:"required"`
+	Semester   string `json:"semester"`
+	WeekStart  string `json:"week_start"`
+	WeekEnd    string `json:"week_end"`
+	CampusCode string `json:"campus_code"`
 }
 
 type SyncEmptyClassroomsResult struct {
@@ -32,10 +32,11 @@ type SyncEmptyClassroomsResult struct {
 
 type EmptyClassroomSyncService interface {
 	SyncUserEmptyClassrooms(ctx context.Context, userID string, req *SyncEmptyClassroomsRequest) (*SyncEmptyClassroomsResult, error)
+	ListClassrooms(userID, semester string) ([]*model.EmptyClassroom, error)
 }
 
 type emptyClassroomSyncService struct {
-	taskManager *runner.TaskManager
+	taskManager   *runner.TaskManager
 	classroomRepo repository.EmptyClassroomRepository
 	logger        *zap.Logger
 }
@@ -46,20 +47,20 @@ func NewEmptyClassroomSyncService(
 	logger *zap.Logger,
 ) EmptyClassroomSyncService {
 	return &emptyClassroomSyncService{
-		taskManager:    taskManager,
-		classroomRepo:  classroomRepo,
-		logger:         logger,
+		taskManager:   taskManager,
+		classroomRepo: classroomRepo,
+		logger:        logger,
 	}
 }
 
 func (s *emptyClassroomSyncService) SyncUserEmptyClassrooms(ctx context.Context, userID string, req *SyncEmptyClassroomsRequest) (*SyncEmptyClassroomsResult, error) {
 	payload := &pb.GetEmptyClassroomPayload{
-		Username:    req.Username,
-		Password:    req.Password,
-		Semester:    req.Semester,
-		WeekStart:   req.WeekStart,
-		WeekEnd:     req.WeekEnd,
-		CampusCode:  req.CampusCode,
+		Username:   req.Username,
+		Password:   req.Password,
+		Semester:   req.Semester,
+		WeekStart:  req.WeekStart,
+		WeekEnd:    req.WeekEnd,
+		CampusCode: req.CampusCode,
 	}
 
 	taskResult, err := s.taskManager.SubmitTaskSync(ctx, pb.TaskType_TASK_TYPE_GET_EMPTY_CLASSROOM, payload)
@@ -133,3 +134,8 @@ func (s *emptyClassroomSyncService) saveClassrooms(ctx context.Context, userID,
 	}
 	return nil
 }
+
+// ListClassrooms 查询用户某学期的空教室。
+func (s *emptyClassroomSyncService) ListClassrooms(userID, semester string) ([]*model.EmptyClassroom, error) {
+	return s.classroomRepo.ListByUserAndSemester(userID, semester)
+}