feat(grpc): add gRPC server infrastructure and schedule sync service

Add gRPC server support with configurable TLS, environment-based settings, and Wire injection. Implement schedule synchronization service with task runner integration for external course data fetching.

- Add gRPC configuration with env var overrides (APP_GRPC_ENABLED, APP_GRPC_PORT, etc.)
- Create gRPC server infrastructure with runner task management
- Implement ScheduleSyncService for course data synchronization
- Add sync endpoint to schedule handler for external system integration
- Update repository with context-aware batch delete operation
- Wire all dependencies including zap logger for structured logging

internal/wire/grpc.go

@@ -0,0 +1,25 @@
+package wire
+
+import (
+	"carrot_bbs/internal/config"
+	"carrot_bbs/internal/grpc/runner"
+
+	"github.com/google/wire"
+	"go.uber.org/zap"
+)
+
+// GRPCSet gRPC 相关的 Provider Set
+var GRPCSet = wire.NewSet(
+	ProvideGRPCServer,
+	ProvideTaskManager,
+)
+
+// ProvideGRPCServer 提供 gRPC 服务器
+func ProvideGRPCServer(cfg *config.Config, logger *zap.Logger) *runner.Server {
+	return runner.NewServer(&cfg.GRPC, logger)
+}
+
+// ProvideTaskManager 提供 TaskManager
+func ProvideTaskManager(server *runner.Server) *runner.TaskManager {
+	return server.GetTaskManager()
+}