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/repository/material_repo.go

@@ -1,9 +1,9 @@
-package repository
+package repository
 
 import (
-	"with_you/internal/dto"
 	"with_you/internal/model"
 	"with_you/internal/pkg/utils"
+	"with_you/internal/query"
 
 	"gorm.io/gorm"
 )
@@ -80,7 +80,7 @@ func (r *materialSubjectRepository) CountMaterials(subjectID string) (int64, err
 
 // MaterialFileRepository 文件资料仓储接口
 type MaterialFileRepository interface {
-	List(params dto.MaterialFileQueryParams) ([]*model.MaterialFile, int64, error)
+	List(params query.MaterialFileQueryParams) ([]*model.MaterialFile, int64, error)
 	GetByID(id string) (*model.MaterialFile, error)
 	GetByIDWithSubject(id string) (*model.MaterialFile, error)
 	Create(file *model.MaterialFile) error
@@ -103,7 +103,7 @@ func NewMaterialFileRepository(db *gorm.DB) MaterialFileRepository {
 }
 
 // List 获取资料列表（支持筛选和分页）
-func (r *materialFileRepository) List(params dto.MaterialFileQueryParams) ([]*model.MaterialFile, int64, error) {
+func (r *materialFileRepository) List(params query.MaterialFileQueryParams) ([]*model.MaterialFile, int64, error) {
 	var files []*model.MaterialFile
 	var total int64
 
@@ -260,4 +260,4 @@ func (r *materialFileRepository) GetLatestMaterials(limit int) ([]*model.Materia
 		Limit(limit).
 		Find(&files).Error
 	return files, err
-}
+}