build(proto): address review feedback

- Swap breaking rule FILE -> WIRE so non-wire-breaking evolution (field
  renames, etc.) is no longer flagged as breaking.
- Strictly enforce buf, protoc-gen-go, and protoc-gen-go-grpc versions in
  check-tools; mismatches now fail rather than warn.
- Fix Proto CI: explicitly fetch refs/remotes/origin/main and compare
  against it (branch=main is not materialized in PR checkouts).

Author: bootjp

.github/workflows/proto.yml

@@ -27,6 +27,9 @@ jobs:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
+      - name: Fetch main for breaking baseline
+        if: github.ref != 'refs/heads/main'
+        run: git fetch --no-tags --prune origin +refs/heads/main:refs/remotes/origin/main
       - uses: actions/setup-go@v6
         with:
           go-version-file: 'go.mod'
@@ -39,7 +42,7 @@ jobs:
       - name: buf breaking (against main)
         if: github.ref != 'refs/heads/main'
         working-directory: proto
-        run: buf breaking --against '../.git#subdir=proto,branch=main'
+        run: buf breaking --against '../.git#subdir=proto,ref=refs/remotes/origin/main'
       - name: buf generate
         working-directory: proto
         run: buf generate

proto/Makefile

@@ -1,5 +1,5 @@
 BUF_VERSION := 1.55.1
-PROTOC_GEN_GO_VERSION := v1.36.11
+PROTOC_GEN_GO_VERSION := 1.36.11
 PROTOC_GEN_GO_GRPC_VERSION := 1.6.1
 
 BUF ?= buf
@@ -15,20 +15,34 @@ check-tools:
 		echo "  go install github.com/bufbuild/buf/cmd/buf@v$(BUF_VERSION)"; \
 		exit 1; \
 	}
-	@installed_buf=$$($(BUF) --version 2>/dev/null); \
-	if [ "$$installed_buf" != "$(BUF_VERSION)" ]; then \
-		echo "warning: buf version mismatch (expected $(BUF_VERSION), got $$installed_buf)"; \
+	@installed=$$($(BUF) --version 2>/dev/null); \
+	if [ "$$installed" != "$(BUF_VERSION)" ]; then \
+		echo "buf version mismatch: expected $(BUF_VERSION), got $$installed"; \
+		echo "install with: go install github.com/bufbuild/buf/cmd/buf@v$(BUF_VERSION)"; \
+		exit 1; \
 	fi
 	@command -v protoc-gen-go >/dev/null 2>&1 || { \
 		echo "protoc-gen-go not found; install with:"; \
-		echo "  go install google.golang.org/protobuf/cmd/protoc-gen-go@$(PROTOC_GEN_GO_VERSION)"; \
+		echo "  go install google.golang.org/protobuf/cmd/protoc-gen-go@v$(PROTOC_GEN_GO_VERSION)"; \
 		exit 1; \
 	}
+	@installed=$$(protoc-gen-go --version 2>/dev/null); \
+	if [ "$$installed" != "protoc-gen-go v$(PROTOC_GEN_GO_VERSION)" ]; then \
+		echo "protoc-gen-go version mismatch: expected v$(PROTOC_GEN_GO_VERSION), got $$installed"; \
+		echo "install with: go install google.golang.org/protobuf/cmd/protoc-gen-go@v$(PROTOC_GEN_GO_VERSION)"; \
+		exit 1; \
+	fi
 	@command -v protoc-gen-go-grpc >/dev/null 2>&1 || { \
 		echo "protoc-gen-go-grpc not found; install with:"; \
 		echo "  go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@v$(PROTOC_GEN_GO_GRPC_VERSION)"; \
 		exit 1; \
 	}
+	@installed=$$(protoc-gen-go-grpc --version 2>/dev/null); \
+	if [ "$$installed" != "protoc-gen-go-grpc $(PROTOC_GEN_GO_GRPC_VERSION)" ]; then \
+		echo "protoc-gen-go-grpc version mismatch: expected $(PROTOC_GEN_GO_GRPC_VERSION), got $$installed"; \
+		echo "install with: go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@v$(PROTOC_GEN_GO_GRPC_VERSION)"; \
+		exit 1; \
+	fi
 
 breaking: check-tools
 	@if git -C .. rev-parse --verify main >/dev/null 2>&1; then \

proto/buf.yaml

@@ -3,4 +3,4 @@ modules:
   - path: .
 breaking:
   use:
-    - FILE
+    - WIRE