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

pkg/readers/sqldir/reader_test.go

@@ -30,18 +30,18 @@ func TestReader_ReadDatabase(t *testing.T) {
 
 	for filename, content := range testFiles {
 		filePath := filepath.Join(tempDir, filename)
-		if err := os.WriteFile(filePath, []byte(content), 0644); err != nil {
+		if err := os.WriteFile(filePath, []byte(content), 0o644); err != nil {
 			t.Fatalf("Failed to create test file %s: %v", filename, err)
 		}
 	}
 
 	// Create subdirectory with additional script
 	subDir := filepath.Join(tempDir, "migrations")
-	if err := os.MkdirAll(subDir, 0755); err != nil {
+	if err := os.MkdirAll(subDir, 0o755); err != nil {
 		t.Fatalf("Failed to create subdirectory: %v", err)
 	}
 	subFile := filepath.Join(subDir, "3_001_add_column.sql")
-	if err := os.WriteFile(subFile, []byte("ALTER TABLE users ADD COLUMN email TEXT;"), 0644); err != nil {
+	if err := os.WriteFile(subFile, []byte("ALTER TABLE users ADD COLUMN email TEXT;"), 0o644); err != nil {
 		t.Fatalf("Failed to create subdirectory file: %v", err)
 	}
 
@@ -141,7 +141,7 @@ func TestReader_ReadSchema(t *testing.T) {
 
 	// Create test SQL file
 	testFile := filepath.Join(tempDir, "1_001_test.sql")
-	if err := os.WriteFile(testFile, []byte("SELECT 1;"), 0644); err != nil {
+	if err := os.WriteFile(testFile, []byte("SELECT 1;"), 0o644); err != nil {
 		t.Fatalf("Failed to create test file: %v", err)
 	}
 
@@ -220,14 +220,14 @@ func TestReader_InvalidFilename(t *testing.T) {
 
 	for _, filename := range invalidFiles {
 		filePath := filepath.Join(tempDir, filename)
-		if err := os.WriteFile(filePath, []byte("SELECT 1;"), 0644); err != nil {
+		if err := os.WriteFile(filePath, []byte("SELECT 1;"), 0o644); err != nil {
 			t.Fatalf("Failed to create test file %s: %v", filename, err)
 		}
 	}
 
 	// Create one valid file
 	validFile := filepath.Join(tempDir, "1_001_valid.sql")
-	if err := os.WriteFile(validFile, []byte("SELECT 1;"), 0644); err != nil {
+	if err := os.WriteFile(validFile, []byte("SELECT 1;"), 0o644); err != nil {
 		t.Fatalf("Failed to create valid file: %v", err)
 	}
 
@@ -277,7 +277,7 @@ func TestReader_HyphenFormat(t *testing.T) {
 
 	for filename, content := range testFiles {
 		filePath := filepath.Join(tempDir, filename)
-		if err := os.WriteFile(filePath, []byte(content), 0644); err != nil {
+		if err := os.WriteFile(filePath, []byte(content), 0o644); err != nil {
 			t.Fatalf("Failed to create test file %s: %v", filename, err)
 		}
 	}
@@ -343,7 +343,7 @@ func TestReader_MixedFormat(t *testing.T) {
 
 	for filename, content := range testFiles {
 		filePath := filepath.Join(tempDir, filename)
-		if err := os.WriteFile(filePath, []byte(content), 0644); err != nil {
+		if err := os.WriteFile(filePath, []byte(content), 0o644); err != nil {
 			t.Fatalf("Failed to create test file %s: %v", filename, err)
 		}
 	}
@@ -386,13 +386,13 @@ func TestReader_SkipSymlinks(t *testing.T) {
 
 	// Create a real SQL file
 	realFile := filepath.Join(tempDir, "1_001_real_file.sql")
-	if err := os.WriteFile(realFile, []byte("SELECT 1;"), 0644); err != nil {
+	if err := os.WriteFile(realFile, []byte("SELECT 1;"), 0o644); err != nil {
 		t.Fatalf("Failed to create real file: %v", err)
 	}
 
 	// Create another file to link to
 	targetFile := filepath.Join(tempDir, "2_001_target.sql")
-	if err := os.WriteFile(targetFile, []byte("SELECT 2;"), 0644); err != nil {
+	if err := os.WriteFile(targetFile, []byte("SELECT 2;"), 0o644); err != nil {
 		t.Fatalf("Failed to create target file: %v", err)
 	}