perfsprint 18→0：strconv.Itoa/FormatInt/FormatUint/FormatBool 替代 fmt.Sprintf、无动词 fmt.Errorf→errors.New、纯字符串拼接。全部语义等价（已核对 diff）。修正 fixer 遗留的 import 问题（引入 goimports 统一整理）。

Result: {"status":"keep","total_issues":56,"golint_canonicalheader":8,"golint_errname":1,"golint_errorlint":12,"golint_forcetypeassert":3,"golint_gosec":0,"golint_intrange":3,"golint_modernize":5,"golint_nilnil":3,"golint_perfsprint":0,"golint_prealloc":3,"golint_recvcheck":7,"golint_usestdlibvars":3,"golint_wastedassign":7,"golint_total":55,"eslint_problems":1,"eslint_errors":0,"eslint_warnings":1,"tsc_errors":0,"measure_s":47}

pkg/pagesarchive/entry.go

@@ -72,14 +72,14 @@ func copyLimited(dst io.Writer, src io.Reader, maxBytes int64) (int64, error) {
 		return written, err
 	}
 	if written > maxBytes {
-		return written, fmt.Errorf("pages file size out of bounds")
+		return written, errors.New("pages file size out of bounds")
 	}
 	return written, nil
 }
 
 func copyAndVerifySize(dst io.Writer, src io.Reader, declaredSize uint64, maxBytes int64) (int64, error) {
 	if declaredSize > uint64(math.MaxInt64) {
-		return 0, fmt.Errorf("pages file size out of bounds")
+		return 0, errors.New("pages file size out of bounds")
 	}
 	written, err := copyLimited(dst, src, maxBytes)
 	if err != nil {

pkg/pagesarchive/extract.go

@@ -124,7 +124,7 @@ func extractEntries(entries []Entry, destDir string, opts ExtractOptions) error
 		appendMeasuredFile(measured, normalizedPath, actual)
 	}
 	if measured.fileCount == 0 {
-		return fmt.Errorf("pages package is empty")
+		return errors.New("pages package is empty")
 	}
 	return nil
 }
@@ -139,7 +139,7 @@ func extractTarFamilyAt(ra io.ReaderAt, size int64, format Format, destDir strin
 		return err
 	}
 	if firstPass.fileCount == 0 {
-		return fmt.Errorf("pages package is empty")
+		return errors.New("pages package is empty")
 	}
 	commonPrefix := ""
 	if opts.StripCommonRoot {
@@ -162,7 +162,7 @@ func extractTarFamilyAt(ra io.ReaderAt, size int64, format Format, destDir strin
 		return extractErr
 	}
 	if secondPass.fileCount != firstPass.fileCount || secondPass.totalSize != firstPass.totalSize {
-		return fmt.Errorf("pages tar package changed between validation and extraction")
+		return errors.New("pages tar package changed between validation and extraction")
 	}
 	return nil
 }

pkg/pagesarchive/format.go

@@ -7,7 +7,7 @@ package pagesarchive
 
 import (
 	"bytes"
-	"fmt"
+	"errors"
 	"path/filepath"
 	"strings"
 )
@@ -87,7 +87,7 @@ func DetectFormat(fileName string, data []byte) (Format, error) {
 	if format, ok := DetectFormatFromBytes(data); ok {
 		return format, nil
 	}
-	return "", fmt.Errorf("unsupported pages package format")
+	return "", errors.New("unsupported pages package format")
 }
 
 // Extension returns the canonical file extension for a format (without leading dot).

pkg/pagesarchive/inspect.go

@@ -137,7 +137,7 @@ func scanTarFamilyAt(
 	enforceLimits bool,
 ) (*measuredArchive, error) {
 	if size < 0 {
-		return nil, fmt.Errorf("invalid pages package size")
+		return nil, errors.New("invalid pages package size")
 	}
 	tarReader, closeReader, err := openTarFamilyReader(io.NewSectionReader(ra, 0, size), format)
 	if err != nil {
@@ -183,7 +183,7 @@ func scanTarReader(tarReader *tar.Reader, limits Limits, enforceLimits bool) (*m
 
 func buildMeasuredManifest(measured *measuredArchive, opts InspectOptions) (*Manifest, error) {
 	if measured == nil || measured.fileCount == 0 {
-		return nil, fmt.Errorf("pages package is empty")
+		return nil, errors.New("pages package is empty")
 	}
 	targetEntryPath, err := resolveTargetEntryPath(opts.RootDir, opts.EntryFile)
 	if err != nil {
@@ -231,7 +231,7 @@ func prepareMeasuredFile(measured *measuredArchive, normalizedPath string, decla
 	}
 	remaining := limits.MaxTotalBytes - measured.totalSize
 	if remaining < 0 || declaredSize > uint64(remaining) { //nolint:gosec // remaining is checked non-negative
-		return fmt.Errorf("pages extracted size exceeds limit")
+		return errors.New("pages extracted size exceeds limit")
 	}
 	return nil
 }

pkg/pagesarchive/list.go

@@ -8,6 +8,7 @@ import (
 	"archive/zip"
 	"compress/bzip2"
 	"compress/gzip"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -52,7 +53,7 @@ func (z sevenZipArchiveFile) Open() (io.ReadCloser, error) {
 // Tar-family archives use the sequential streaming paths in inspect.go/extract.go.
 func listRandomAccessEntriesAt(ra io.ReaderAt, size int64, format Format) ([]Entry, error) {
 	if size < 0 {
-		return nil, fmt.Errorf("invalid pages package size")
+		return nil, errors.New("invalid pages package size")
 	}
 	switch format {
 	case FormatZip:

pkg/pagesarchive/path.go

@@ -4,6 +4,7 @@
 package pagesarchive
 
 import (
+	"errors"
 	"fmt"
 	"path"
 	"strings"
@@ -18,7 +19,7 @@ func NormalizeLogicalPath(raw string, allowEmpty bool) (string, error) {
 		if allowEmpty {
 			return "", nil
 		}
-		return "", fmt.Errorf("pages path is required")
+		return "", errors.New("pages path is required")
 	}
 	if err := validateLogicalPathText(raw); err != nil {
 		return "", err
@@ -29,7 +30,7 @@ func NormalizeLogicalPath(raw string, allowEmpty bool) (string, error) {
 		if allowEmpty {
 			return "", nil
 		}
-		return "", fmt.Errorf("pages path is required")
+		return "", errors.New("pages path is required")
 	}
 	if strings.HasPrefix(cleaned, "/") || cleaned == ".." || strings.HasPrefix(cleaned, "../") {
 		return "", fmt.Errorf("pages path escapes directory: %s", raw)
@@ -39,7 +40,7 @@ func NormalizeLogicalPath(raw string, allowEmpty bool) (string, error) {
 
 func validateLogicalPathText(raw string) error {
 	if !utf8.ValidString(raw) {
-		return fmt.Errorf("pages path is not valid UTF-8")
+		return errors.New("pages path is not valid UTF-8")
 	}
 	if strings.Contains(raw, "\\") {
 		return fmt.Errorf("pages path must use POSIX separators: %s", raw)
@@ -56,7 +57,7 @@ func validateLogicalPathText(raw string) error {
 func validateLogicalPathRunes(raw string) error {
 	for _, r := range raw {
 		if r == 0 || unicode.IsControl(r) {
-			return fmt.Errorf("pages path contains a control character")
+			return errors.New("pages path contains a control character")
 		}
 		if r == '\'' || r == '"' || r == ';' {
 			return fmt.Errorf("pages path contains an unsupported character: %s", raw)