chore(ci): add govulncheck, staticcheck, go vet, gofumpt gates

* Add lint/format checks to the Gitea release workflow and Makefile
  (targets: vet, fmt, fmt-check, staticcheck, govulncheck, check)
* Switch .golangci.json formatter from gofmt to gofumpt (extra.group-params)
* Bump golang.org/x/text 0.37.0 -> 0.39.0 for GO-2026-5970; re-vendor
* Fix staticcheck S1011 in pkg/diff; drop unused pgsql writer helpers
* Fix gocritic unnamedResult (pkg/diff) and rangeValCopy (pkg/pgsql)
* Apply gofumpt + goimports formatting across the tree

cmd/relspec/convert_from_list_test.go

@@ -46,7 +46,7 @@ func TestReadDatabaseListForConvert_MultipleFiles(t *testing.T) {
 
 func TestReadDatabaseListForConvert_PathWithSpaces(t *testing.T) {
 	spacedDir := filepath.Join(t.TempDir(), "my schema files")
-	if err := os.MkdirAll(spacedDir, 0755); err != nil {
+	if err := os.MkdirAll(spacedDir, 0o755); err != nil {
 		t.Fatal(err)
 	}
 	file := filepath.Join(spacedDir, "my users schema.json")
@@ -63,7 +63,7 @@ func TestReadDatabaseListForConvert_PathWithSpaces(t *testing.T) {
 
 func TestReadDatabaseListForConvert_MultipleFilesPathWithSpaces(t *testing.T) {
 	spacedDir := filepath.Join(t.TempDir(), "my schema files")
-	if err := os.MkdirAll(spacedDir, 0755); err != nil {
+	if err := os.MkdirAll(spacedDir, 0o755); err != nil {
 		t.Fatal(err)
 	}
 	file1 := filepath.Join(spacedDir, "users schema.json")
@@ -154,7 +154,7 @@ func TestRunConvert_FromListEndToEndPathWithSpaces(t *testing.T) {
 	defer restoreConvertState(saved)
 
 	spacedDir := filepath.Join(t.TempDir(), "my schema dir")
-	if err := os.MkdirAll(spacedDir, 0755); err != nil {
+	if err := os.MkdirAll(spacedDir, 0o755); err != nil {
 		t.Fatal(err)
 	}
 	file1 := filepath.Join(spacedDir, "users schema.json")

cmd/relspec/inspect.go

@@ -193,7 +193,7 @@ func runInspect(cmd *cobra.Command, args []string) error {
 
 	// Write output
 	if inspectOutputPath != "" {
-		err = os.WriteFile(inspectOutputPath, []byte(formattedReport), 0644)
+		err = os.WriteFile(inspectOutputPath, []byte(formattedReport), 0o644)
 		if err != nil {
 			return fmt.Errorf("failed to write output file: %w", err)
 		}

cmd/relspec/merge.go

@@ -158,9 +158,7 @@ func runMerge(cmd *cobra.Command, args []string) error {
 		}
 		mergeTargetPath = expandPath(mergeTargetPath)
 	} else if mergeTargetConn == "" {
-
 		return fmt.Errorf("--target-conn is required for pgsql format")
-
 	}
 
 	if mergeSourceType != "pgsql" {

cmd/relspec/merge_from_list_test.go

@@ -105,7 +105,7 @@ func TestRunMerge_FromListPathWithSpaces(t *testing.T) {
 	defer restoreMergeState(saved)
 
 	spacedDir := filepath.Join(t.TempDir(), "my schema files")
-	if err := os.MkdirAll(spacedDir, 0755); err != nil {
+	if err := os.MkdirAll(spacedDir, 0o755); err != nil {
 		t.Fatal(err)
 	}
 	targetFile := filepath.Join(spacedDir, "target schema.json")

cmd/relspec/templ_from_list_test.go

@@ -10,7 +10,7 @@ import (
 func writeTestTemplate(t *testing.T, path string) {
 	t.Helper()
 	content := []byte(`{{.Name}}`)
-	if err := os.WriteFile(path, content, 0644); err != nil {
+	if err := os.WriteFile(path, content, 0o644); err != nil {
 		t.Fatalf("failed to write template file %s: %v", path, err)
 	}
 }
@@ -104,7 +104,7 @@ func TestRunTempl_FromListPathWithSpaces(t *testing.T) {
 	defer restoreTemplState(saved)
 
 	spacedDir := filepath.Join(t.TempDir(), "my schema files")
-	if err := os.MkdirAll(spacedDir, 0755); err != nil {
+	if err := os.MkdirAll(spacedDir, 0o755); err != nil {
 		t.Fatal(err)
 	}
 	file1 := filepath.Join(spacedDir, "users schema.json")

cmd/relspec/testhelpers_test.go

@@ -66,7 +66,7 @@ func writeTestJSON(t *testing.T, path string, tableNames []string) {
 	if err != nil {
 		t.Fatalf("failed to marshal test JSON: %v", err)
 	}
-	if err := os.WriteFile(path, data, 0644); err != nil {
+	if err := os.WriteFile(path, data, 0o644); err != nil {
 		t.Fatalf("failed to write test file %s: %v", path, err)
 	}
 }
@@ -100,7 +100,7 @@ func writeTestJSONWithSingleColumnType(t *testing.T, path, tableName, columnType
 	if err != nil {
 		t.Fatalf("failed to marshal test JSON: %v", err)
 	}
-	if err := os.WriteFile(path, data, 0644); err != nil {
+	if err := os.WriteFile(path, data, 0o644); err != nil {
 		t.Fatalf("failed to write test file %s: %v", path, err)
 	}
 }