refactor: cleanup unused code and simplify internal packages

This commit performs a significant cleanup of the codebase by removing unused functions, methods, and entire files across various internal modules. This reduces technical debt and simplifies the project structure.

Key changes include:
- **cache**: Removed unused cache key generators and metrics snapshots.
- **dto**: Removed redundant converter functions and segment creation helpers.
- **middleware**: Deleted the unused `logger.go` middleware and simplified `ratelimit.go` and `casbin.go`.
- **model**: Removed unused ID helpers, database closing functions, and batch decryption logic.
- **pkg**: Cleaned up unused utility functions in `circuitbreaker`, `crypto`, `cursor`, `hook`, and `utils`.
- **service**: Deleted `account_cleanup_service.go` and removed unused helper functions in `log_cleanup_service.go` and `sensitive_service.go`.
- **repository**: Removed unused private loading methods in `comment_repo.go`.

internal/grpc/runner/server.go

@@ -1,7 +1,6 @@
 package runner
 
 import (
-	"context"
 	"fmt"
 	"net"
 	"time"
@@ -12,7 +11,6 @@ import (
 	"go.uber.org/zap"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/credentials/insecure"
 )
 
 // Server gRPC 服务器
@@ -23,19 +21,6 @@ type Server struct {
 	grpcSrv *grpc.Server
 }
 
-// NewServer 创建新的 gRPC 服务器（内部构造 Hub + TaskManager）
-func NewServer(cfg *config.GRPCConfig, logger *zap.Logger) *Server {
-	taskManager := NewTaskManager(nil, 60*time.Second, logger)
-	hub := NewRunnerHub(taskManager, logger)
-	taskManager.SetDispatcher(hub)
-
-	return &Server{
-		cfg:    cfg,
-		logger: logger,
-		hub:    hub,
-	}
-}
-
 // NewServerWithDeps 使用外部依赖创建 gRPC 服务器（Wire DI 使用）
 func NewServerWithDeps(cfg *config.GRPCConfig, logger *zap.Logger, hub *RunnerHub) *Server {
 	return &Server{
@@ -111,43 +96,3 @@ func (s *Server) Stop() {
 	}
 }
 
-// GetHub 获取 RunnerHub
-func (s *Server) GetHub() *RunnerHub {
-	return s.hub
-}
-
-// GetTaskManager 获取 TaskManager
-func (s *Server) GetTaskManager() *TaskManager {
-	return s.hub.taskManager
-}
-
-// Shutdown 优雅关闭
-func (s *Server) Shutdown(ctx context.Context) error {
-	if s.grpcSrv == nil {
-		return nil
-	}
-
-	done := make(chan struct{})
-	go func() {
-		s.grpcSrv.GracefulStop()
-		close(done)
-	}()
-
-	select {
-	case <-done:
-		s.logger.Info("gRPC server stopped gracefully")
-		return nil
-	case <-ctx.Done():
-		s.logger.Warn("gRPC server shutdown timeout, forcing stop")
-		s.grpcSrv.Stop()
-		return ctx.Err()
-	}
-}
-
-// GetClientCredentials 获取客户端凭证配置
-func GetClientCredentials(cfg *config.GRPCConfig) (credentials.TransportCredentials, error) {
-	if cfg.TLSEnabled {
-		return credentials.NewClientTLSFromFile(cfg.TLSCertFile, "")
-	}
-	return insecure.NewCredentials(), nil
-}