refactor: 重构代码架构并使用 Modern Go 特性

- 重命名模块 jwts -> schedule_converter
- 新增 service 包，统一业务逻辑层
- 新增 pkg/logger 包，使用 slog 结构化日志
- 新增 pkg/errors 包，统一错误处理
- 拆分 captcha 包，图片识别移至 service/recognizer
- 清理 models 包，只保留数据结构定义
- 消除 grpc/handler.go 中的重复代码
- 简化 main.go，使用 slog 和 context
- 配置支持单例模式和结构化配置
- 使用 any 替代 interface{}
- 使用 sync.Map 替代 map + RWMutex

proto/runner/runner_grpc.pb.go

@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go-grpc. DO NOT EDIT.
 // versions:
-// - protoc-gen-go-grpc v1.6.1
-// - protoc             v6.33.1
+// - protoc-gen-go-grpc v1.5.1
+// - protoc             v3.19.4
 // source: proto/runner/runner.proto
 
 package runner
@@ -76,7 +76,7 @@ type RunnerHubServer interface {
 type UnimplementedRunnerHubServer struct{}
 
 func (UnimplementedRunnerHubServer) Connect(grpc.BidiStreamingServer[StreamMessage, StreamMessage]) error {
-	return status.Error(codes.Unimplemented, "method Connect not implemented")
+	return status.Errorf(codes.Unimplemented, "method Connect not implemented")
 }
 func (UnimplementedRunnerHubServer) mustEmbedUnimplementedRunnerHubServer() {}
 func (UnimplementedRunnerHubServer) testEmbeddedByValue()                   {}
@@ -89,7 +89,7 @@ type UnsafeRunnerHubServer interface {
 }
 
 func RegisterRunnerHubServer(s grpc.ServiceRegistrar, srv RunnerHubServer) {
-	// If the following call panics, it indicates UnimplementedRunnerHubServer was
+	// If the following call pancis, it indicates UnimplementedRunnerHubServer was
 	// embedded by pointer and is nil.  This will cause panics if an
 	// unimplemented method is ever invoked, so we test this at initialization
 	// time to prevent it from happening at runtime later due to I/O.