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/vote_service.go

@@ -8,20 +8,30 @@ 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/hook"
 	"with_you/internal/repository"
 )
 
-// VoteService 投票服务
-type VoteService struct {
+// VoteService 投票服务接口
+type VoteService interface {
+	CreateVotePost(ctx context.Context, userID string, req *dto.CreateVotePostRequest) (*dto.PostResponse, error)
+	GetVoteOptions(postID string) ([]dto.VoteOptionDTO, error)
+	GetVoteResult(postID, userID string) (*dto.VoteResultDTO, error)
+	Vote(ctx context.Context, postID, userID, optionID string) error
+	Unvote(ctx context.Context, postID, userID string) error
+	UpdateVoteOption(ctx context.Context, postID, optionID, userID, content string) error
+}
+
+// voteService 投票服务实现
+type voteService struct {
 	voteRepo             repository.VoteRepository
 	postRepo             repository.PostRepository
 	cache                cache.Cache
-	postAIService        *PostAIService
+	postAIService        PostAIService
 	systemMessageService SystemMessageService
 	hookManager          *hook.Manager
 	logService           *LogService
@@ -31,12 +41,12 @@ func NewVoteService(
 	voteRepo repository.VoteRepository,
 	postRepo repository.PostRepository,
 	cache cache.Cache,
-	postAIService *PostAIService,
+	postAIService PostAIService,
 	systemMessageService SystemMessageService,
 	hookManager *hook.Manager,
 	logService *LogService,
-) *VoteService {
-	return &VoteService{
+) VoteService {
+	return &voteService{
 		voteRepo:             voteRepo,
 		postRepo:             postRepo,
 		cache:                cache,
@@ -48,7 +58,7 @@ func NewVoteService(
 }
 
 // CreateVotePost 创建投票帖子
-func (s *VoteService) CreateVotePost(ctx context.Context, userID string, req *dto.CreateVotePostRequest) (*dto.PostResponse, error) {
+func (s *voteService) CreateVotePost(ctx context.Context, userID string, req *dto.CreateVotePostRequest) (*dto.PostResponse, error) {
 	if len(req.VoteOptions) < 2 {
 		return nil, errors.New("投票选项至少需要2个")
 	}
@@ -108,7 +118,7 @@ func (s *VoteService) CreateVotePost(ctx context.Context, userID string, req *dt
 	return s.convertToPostResponse(createdPost, userID), nil
 }
 
-func (s *VoteService) reviewVotePostAsync(postID, userID, title, content string, images []string) {
+func (s *voteService) reviewVotePostAsync(postID, userID, title, content string, images []string) {
 	defer func() {
 		if r := recover(); r != nil {
 			log.Printf("[ERROR] Panic in vote post moderation async flow, fallback publish post=%s panic=%v", postID, r)
@@ -183,7 +193,7 @@ func (s *VoteService) reviewVotePostAsync(postID, userID, title, content string,
 	cache.InvalidatePostList(s.cache)
 }
 
-func (s *VoteService) updateModerationStatusWithRetry(postID string, status model.PostStatus, rejectReason string, reviewedBy string) error {
+func (s *voteService) updateModerationStatusWithRetry(postID string, status model.PostStatus, rejectReason string, reviewedBy string) error {
 	const maxAttempts = 3
 	const retryDelay = 200 * time.Millisecond
 
@@ -203,7 +213,7 @@ func (s *VoteService) updateModerationStatusWithRetry(postID string, status mode
 	return lastErr
 }
 
-func (s *VoteService) notifyModerationRejected(userID, reason string) {
+func (s *voteService) notifyModerationRejected(userID, reason string) {
 	if s.systemMessageService == nil || strings.TrimSpace(userID) == "" {
 		return
 	}
@@ -224,7 +234,7 @@ func (s *VoteService) notifyModerationRejected(userID, reason string) {
 }
 
 // resolveVoteOptions 解析投票选项（优先从 segments 读取，兼容旧数据从 vote_options 表读取）
-func (s *VoteService) resolveVoteOptions(postID string, segments model.MessageSegments) ([]dto.VoteOptionDTO, error) {
+func (s *voteService) resolveVoteOptions(postID string, segments model.MessageSegments) ([]dto.VoteOptionDTO, error) {
 	if len(segments) > 0 {
 		voteData := dto.ExtractVoteSegmentData(segments)
 		if voteData != nil {
@@ -262,7 +272,7 @@ func (s *VoteService) resolveVoteOptions(postID string, segments model.MessageSe
 }
 
 // GetVoteOptions 获取投票选项（优先从 segments 读取，兼容旧数据从 vote_options 表读取）
-func (s *VoteService) GetVoteOptions(postID string) ([]dto.VoteOptionDTO, error) {
+func (s *voteService) GetVoteOptions(postID string) ([]dto.VoteOptionDTO, error) {
 	post, err := s.postRepo.GetByID(postID)
 	if err != nil {
 		return nil, err
@@ -272,7 +282,7 @@ func (s *VoteService) GetVoteOptions(postID string) ([]dto.VoteOptionDTO, error)
 }
 
 // GetVoteResult 获取投票结果（包含用户投票状态）
-func (s *VoteService) GetVoteResult(postID, userID string) (*dto.VoteResultDTO, error) {
+func (s *voteService) GetVoteResult(postID, userID string) (*dto.VoteResultDTO, error) {
 	post, err := s.postRepo.GetByID(postID)
 	if err != nil {
 		return nil, err
@@ -306,7 +316,7 @@ func (s *VoteService) GetVoteResult(postID, userID string) (*dto.VoteResultDTO,
 }
 
 // Vote 投票
-func (s *VoteService) Vote(ctx context.Context, postID, userID, optionID string) error {
+func (s *voteService) Vote(ctx context.Context, postID, userID, optionID string) error {
 	// 调用voteRepo.Vote
 	err := s.voteRepo.Vote(postID, userID, optionID)
 	if err != nil {
@@ -320,7 +330,7 @@ func (s *VoteService) Vote(ctx context.Context, postID, userID, optionID string)
 }
 
 // Unvote 取消投票
-func (s *VoteService) Unvote(ctx context.Context, postID, userID string) error {
+func (s *voteService) Unvote(ctx context.Context, postID, userID string) error {
 	// 调用voteRepo.Unvote
 	err := s.voteRepo.Unvote(postID, userID)
 	if err != nil {
@@ -334,7 +344,7 @@ func (s *VoteService) Unvote(ctx context.Context, postID, userID string) error {
 }
 
 // UpdateVoteOption 更新投票选项（作者权限）
-func (s *VoteService) UpdateVoteOption(ctx context.Context, postID, optionID, userID, content string) error {
+func (s *voteService) UpdateVoteOption(ctx context.Context, postID, optionID, userID, content string) error {
 	// 获取帖子信息
 	post, err := s.postRepo.GetByID(postID)
 	if err != nil {
@@ -351,7 +361,7 @@ func (s *VoteService) UpdateVoteOption(ctx context.Context, postID, optionID, us
 }
 
 // convertToPostResponse 将Post模型转换为PostResponse DTO
-func (s *VoteService) convertToPostResponse(post *model.Post, currentUserID string) *dto.PostResponse {
+func (s *voteService) convertToPostResponse(post *model.Post, currentUserID string) *dto.PostResponse {
 	if post == nil {
 		return nil
 	}