feat: basic GRPC plugin interface

go.mod

go.sum

pkg/analyzer/commit/commit_analyzer.pb.go

pkg/analyzer/commit/commit_analyzer.proto

pkg/analyzer/commit/commit_analyzer_grpc.pb.go

pkg/analyzer/commit/plugin/plugin.go

pkg/plugin/client.go

pkg/plugin/serve.go

pkg/plugin/wrapper/commit_analyzer.go

pkg/plugin/wrapper/grpc.go