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/handler/user_handler.go

@@ -36,7 +36,7 @@ type UserHandler struct {
 	userService         service.UserService
 	activityService     service.UserActivityService
 	profileAuditService service.UserProfileAuditService
-	jwtService          *service.JWTService
+	jwtService          service.JWTService
 	logService          *service.LogService
 }
 
@@ -53,7 +53,7 @@ func (h *UserHandler) SetProfileAuditService(profileAuditService service.UserPro
 }
 
 // SetJWTService 设置JWT服务
-func (h *UserHandler) SetJWTService(jwtService *service.JWTService) {
+func (h *UserHandler) SetJWTService(jwtService service.JWTService) {
 	h.jwtService = jwtService
 }