Apply mechanical lint fixes for golangci-lint v2.12.2 rollout

Auto-remediate style-only findings (wsl_v5, nlreturn, noinlineerr,
modernize, intrange, perfsprint, usetesting, unconvert, errorlint,
gocritic, testifylint) and rename printf-style helpers to f-suffixed
names (goprintffuncname): ui.Writer message methods, cli.ReportErrorf,
database.Fatalf, vaultik stdoutf.

internal/vaultik/restore_locality_test.go

@@ -6,6 +6,7 @@ import (
 	"crypto/rand"
 	"fmt"
 	"io"
+	"maps"
 	"os"
 	"path/filepath"
 	"sort"
@@ -55,6 +56,7 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 	fs := afero.NewOsFs()
 	tempDir, err := os.MkdirTemp("", "vaultik-locality-")
 	require.NoError(t, err)
+
 	defer func() { _ = os.RemoveAll(tempDir) }()
 
 	dataDir := filepath.Join(tempDir, "source")
@@ -86,8 +88,9 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 		path string
 		data []byte
 	}
+
 	sources := make([]*source, srcCount)
-	for i := 0; i < srcCount; i++ {
+	for i := range srcCount {
 		s := &source{
 			path: fmt.Sprintf("src-%03d.bin", i+1),
 			data: randomBytes(t, srcBytes),
@@ -105,11 +108,14 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 		sourceBlob  int // 0, 1, or 2
 		sourceIndex int // index into sources slice
 	}
+
 	groupReps := []int{0, perBlob, 2 * perBlob} // 0, 5, 10
 	letters := []byte{'A', 'B', 'C'}
+
 	var copies []copyFile
-	for i := 0; i < 3; i++ {
-		for j := 0; j < blobsCount; j++ {
+
+	for i := range 3 {
+		for j := range blobsCount {
 			seq := i*blobsCount + j + 1
 			name := fmt.Sprintf("cp-%03d-%c.bin", seq, letters[j])
 			path := filepath.Join(dataDir, name)
@@ -143,6 +149,7 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 
 	db, err := database.New(ctx, dbPath)
 	require.NoError(t, err)
+
 	defer func() { _ = db.Close() }()
 
 	repos := database.NewRepositories(db)
@@ -187,6 +194,7 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 	// immediately before close) so we read PeakLen and call counters
 	// from the same instance the production code used.
 	var cacheRef *blobDiskCache
+
 	v := &Vaultik{
 		Config:  cfg,
 		Storage: counter,
@@ -214,6 +222,7 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 		require.NoErrorf(t, err, "source missing after restore: %s", s.path)
 		require.Truef(t, bytes.Equal(got, s.data), "byte mismatch for source %s", s.path)
 	}
+
 	for _, c := range copies {
 		restored := filepath.Join(restoreDir, c.path)
 		got, err := afero.ReadFile(fs, restored)
@@ -226,6 +235,7 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 		if !filterBlobKey(key) {
 			continue
 		}
+
 		assert.Equalf(t, 1, n, "blob %s fetched %d times, want exactly 1", key, n)
 	}
 
@@ -248,9 +258,11 @@ func TestRestoreLocalityAndReadAt(t *testing.T) {
 // chunker picks non-degenerate FastCDC boundaries.
 func randomBytes(t *testing.T, n int) []byte {
 	t.Helper()
+
 	b := make([]byte, n)
 	_, err := rand.Read(b)
 	require.NoError(t, err)
+
 	return b
 }
 
@@ -258,21 +270,27 @@ func randomBytes(t *testing.T, n int) []byte {
 // relative keys for every blob file present.
 func listBlobKeys(t *testing.T, storeDir string) []string {
 	t.Helper()
+
 	var keys []string
+
 	root := filepath.Join(storeDir, "blobs")
 	err := filepath.Walk(root, func(p string, info os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}
+
 		if info.IsDir() {
 			return nil
 		}
+
 		rel, _ := filepath.Rel(storeDir, p)
 		keys = append(keys, rel)
+
 		return nil
 	})
 	require.NoError(t, err)
 	sort.Strings(keys)
+
 	return keys
 }
 
@@ -289,6 +307,7 @@ func filterBlobKey(key string) bool {
 // vaultik for access to unexported cache internals.
 type countingStorerInternal struct {
 	storage.Storer
+
 	mu     sync.Mutex
 	counts map[string]int
 }
@@ -301,15 +320,16 @@ func (c *countingStorerInternal) Get(ctx context.Context, key string) (io.ReadCl
 	c.mu.Lock()
 	c.counts[key]++
 	c.mu.Unlock()
+
 	return c.Storer.Get(ctx, key)
 }
 
 func (c *countingStorerInternal) snapshot() map[string]int {
 	c.mu.Lock()
 	defer c.mu.Unlock()
+
 	out := make(map[string]int, len(c.counts))
-	for k, v := range c.counts {
-		out[k] = v
-	}
+	maps.Copy(out, c.counts)
+
 	return out
 }