fix: pre-commit Go lint 按包目录分组执行，修复测试文件 typecheck 失败

将逐文件 lint 改为按包目录去重分组，同包的 _test.go 与被测文件在同一轮
typecheck 中参与分析，避免 undefined 错误。

Makefile

@@ -98,7 +98,9 @@ _hooks-pre-commit:
 		printf 'No staged files to check\n'; \
 		exit 0; \
 	fi; \
-	printf '%s\n' "$$staged_files" | while IFS= read -r file; do \
+	backend_pkgs=''; \
+	versionctl_pkgs=''; \
+	for file in $$staged_files; do \
 		[ -n "$$file" ] || continue; \
 		case "$$file" in scripts/git-hooks/*) continue ;; esac; \
 		if git show ":$$file" 2>/dev/null | grep -Eq '^(<<<<<<<|=======|>>>>>>>)'; then \
@@ -114,14 +116,12 @@ _hooks-pre-commit:
 		fi; \
 		case "$$file" in \
 			backend/*.go) \
-				rel=$${file#backend/}; \
-				printf 'Go lint: backend/%s\n' "$$rel"; \
-				(cd backend && go tool golangci-lint run "$$rel"); \
+				dir=$$(dirname "$${file#backend/}"); \
+				case " $$backend_pkgs " in *" $$dir "*) ;; *) backend_pkgs="$$backend_pkgs $$dir" ;; esac; \
 				;; \
 			versionctl/*.go) \
-				rel=$${file#versionctl/}; \
-				printf 'Go lint: versionctl/%s\n' "$$rel"; \
-				(cd versionctl && go tool golangci-lint run "$$rel"); \
+				dir=$$(dirname "$${file#versionctl/}"); \
+				case " $$versionctl_pkgs " in *" $$dir "*) ;; *) versionctl_pkgs="$$versionctl_pkgs $$dir" ;; esac; \
 				;; \
 			frontend/*.ts|frontend/*.tsx) \
 				rel=$${file#frontend/}; \
@@ -137,6 +137,14 @@ _hooks-pre-commit:
 				;; \
 		esac; \
 	done; \
+	for dir in $$backend_pkgs; do \
+		printf 'Go lint: backend/%s\n' "$$dir"; \
+		(cd backend && go tool golangci-lint run "$$dir/"); \
+	done; \
+	for dir in $$versionctl_pkgs; do \
+		printf 'Go lint: versionctl/%s\n' "$$dir"; \
+		(cd versionctl && go tool golangci-lint run "$$dir/"); \
+	done; \
 	printf 'Pre-commit checks passed\n'
 
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