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/post_service.go

@@ -8,9 +8,9 @@ import (
 	"strings"
 	"time"
 
-	apperrors "with_you/internal/errors"
 	"with_you/internal/cache"
 	"with_you/internal/dto"
+	apperrors "with_you/internal/errors"
 	"with_you/internal/model"
 	"with_you/internal/pkg/cursor"
 	"with_you/internal/pkg/hook"
@@ -75,13 +75,13 @@ type postServiceImpl struct {
 	postRepo             repository.PostRepository
 	systemMessageService SystemMessageService
 	cache                cache.Cache
-	postAIService        *PostAIService
+	postAIService        PostAIService
 	txManager            repository.TransactionManager
 	logService           *LogService
 	hookManager          *hook.Manager
 }
 
-func NewPostService(postRepo repository.PostRepository, systemMessageService SystemMessageService, postAIService *PostAIService, cacheBackend cache.Cache, txManager repository.TransactionManager, hookManager *hook.Manager, logService *LogService) PostService {
+func NewPostService(postRepo repository.PostRepository, systemMessageService SystemMessageService, postAIService PostAIService, cacheBackend cache.Cache, txManager repository.TransactionManager, hookManager *hook.Manager, logService *LogService) PostService {
 	return &postServiceImpl{
 		postRepo:             postRepo,
 		systemMessageService: systemMessageService,