Restructure Stovepipe under gateway and add core/extension placeholders.

Move proto, generated gRPC Go, and controllers into stovepipe/gateway; add
stovepipe/orchestrator, entity, and extension stubs; introduce core/extension
for shared extensions. Update Makefile proto paths, Gazelle resolve, examples,
and integration tests. Drop committed stovepipe.pb.yarpc.go (regenerate via
make proto when YARPC is needed). SubmitQueue gateway/orchestrator unchanged.

Author: mnoah1

BUILD.bazel

@@ -5,7 +5,7 @@ load("@gazelle//:def.bzl", "gazelle")
 # Resolve protobuf import ambiguities - use the actual protopb packages, not the proto aliases
 # gazelle:resolve go github.com/uber/submitqueue/gateway/protopb //gateway/protopb
 # gazelle:resolve go github.com/uber/submitqueue/orchestrator/protopb //orchestrator/protopb
-# gazelle:resolve go github.com/uber/submitqueue/stovepipe/protopb //stovepipe/protopb
+# gazelle:resolve go github.com/uber/submitqueue/stovepipe/gateway/protopb //stovepipe/gateway/protopb
 
 # Export marker files for test data dependencies (used by FindRepoRoot in tests)
 exports_files(

Makefile

@@ -91,7 +91,7 @@ clean-proto: ## Clean generated proto files
 	@echo "Cleaning generated proto files..."
 	@rm -rf gateway/protopb/*.pb.go
 	@rm -rf orchestrator/protopb/*.pb.go
-	@rm -rf stovepipe/protopb/*.pb.go
+	@rm -rf stovepipe/gateway/protopb/*.pb.go
 	@echo "Proto clean complete!"
 
 deps: tidy-go ## Download and tidy Go dependencies
@@ -287,10 +287,10 @@ proto: ## Generate protobuf files from .proto definitions
 	  --go-grpc_out=orchestrator/protopb --go-grpc_opt=paths=source_relative \
 	  --yarpc-go_out=orchestrator/protopb --yarpc-go_opt=paths=source_relative \
 	  --proto_path=orchestrator/proto orchestrator/proto/orchestrator.proto
-	@protoc --go_out=stovepipe/protopb --go_opt=paths=source_relative \
-	  --go-grpc_out=stovepipe/protopb --go-grpc_opt=paths=source_relative \
-	  --yarpc-go_out=stovepipe/protopb --yarpc-go_opt=paths=source_relative \
-	  --proto_path=stovepipe/proto stovepipe/proto/stovepipe.proto
+	@protoc --go_out=stovepipe/gateway/protopb --go_opt=paths=source_relative \
+	  --go-grpc_out=stovepipe/gateway/protopb --go-grpc_opt=paths=source_relative \
+	  --yarpc-go_out=stovepipe/gateway/protopb --yarpc-go_opt=paths=source_relative \
+	  --proto_path=stovepipe/gateway/proto stovepipe/gateway/proto/stovepipe.proto
 	@echo "Protobuf files generated successfully!"
 
 # Bazel query helpers

core/extension/BUILD.bazel

@@ -0,0 +1,8 @@
+load("@rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "extension",
+    srcs = ["doc.go"],
+    importpath = "github.com/uber/submitqueue/core/extension",
+    visibility = ["//visibility:public"],
+)

core/extension/doc.go

@@ -0,0 +1,17 @@
+// Copyright (c) 2025 Uber Technologies, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package extension holds extension interfaces and implementations shared
+// across SubmitQueue, Stovepipe, and other repo-local services.
+package extension

example/client/stovepipe/BUILD.bazel

@@ -6,7 +6,7 @@ go_library(
     importpath = "github.com/uber/submitqueue/example/client/stovepipe",
     visibility = ["//visibility:private"],
     deps = [
-        "//stovepipe/protopb",
+        "//stovepipe/gateway/protopb",
         "@org_golang_google_grpc//:grpc",
         "@org_golang_google_grpc//credentials/insecure",
     ],

example/client/stovepipe/main.go

@@ -21,7 +21,7 @@ import (
 	"os"
 	"time"
 
-	pb "github.com/uber/submitqueue/stovepipe/protopb"
+	pb "github.com/uber/submitqueue/stovepipe/gateway/protopb"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 )

example/server/stovepipe/BUILD.bazel

@@ -11,8 +11,8 @@ go_library(
     importpath = "github.com/uber/submitqueue/example/server/stovepipe",
     visibility = ["//visibility:private"],
     deps = [
-        "//stovepipe/controller",
-        "//stovepipe/protopb",
+        "//stovepipe/gateway/controller",
+        "//stovepipe/gateway/protopb",
         "@com_github_uber_go_tally_v4//:tally",
         "@org_golang_google_grpc//:grpc",
         "@org_golang_google_grpc//reflection",

example/server/stovepipe/main.go

@@ -26,8 +26,8 @@ import (
 	"time"
 
 	"github.com/uber-go/tally/v4"
-	"github.com/uber/submitqueue/stovepipe/controller"
-	pb "github.com/uber/submitqueue/stovepipe/protopb"
+	"github.com/uber/submitqueue/stovepipe/gateway/controller"
+	pb "github.com/uber/submitqueue/stovepipe/gateway/protopb"
 	"go.uber.org/zap"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/reflection"

stovepipe/README.md

@@ -1 +1,8 @@
-SubmitQueue Stovepipe
+# Stovepipe
+
+Stovepipe service layout:
+
+- `gateway/` — RPC surface, gateway controllers, and generated protobufs
+- `orchestrator/` — reserved for the future Stovepipe orchestrator binary
+- `extension/` — Stovepipe-specific extension implementations
+- `entity/` — Stovepipe-specific domain entities

stovepipe/entity/BUILD.bazel

@@ -0,0 +1,8 @@
+load("@rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "entity",
+    srcs = ["doc.go"],
+    importpath = "github.com/uber/submitqueue/stovepipe/entity",
+    visibility = ["//visibility:public"],
+)