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}

internal/apps/admin/status/routers.go

@@ -14,6 +14,7 @@ import (
 	"os"
 	"os/exec"
 	"runtime"
+	"strconv"
 	"time"
 
 	"github.com/Rain-kl/Wavelet/internal/infra/config"
@@ -309,7 +310,7 @@ func exportSQLite(c *gin.Context) {
 
 	c.Header("Content-Disposition", `attachment; filename="openflare.db"`)
 	c.Header("Content-Type", "application/octet-stream")
-	c.Header("Content-Length", fmt.Sprintf("%d", fi.Size()))
+	c.Header("Content-Length", strconv.FormatInt(fi.Size(), 10))
 	c.Status(http.StatusOK)
 	http.ServeContent(c.Writer, c.Request, "openflare.db", fi.ModTime(), f)
 }
@@ -328,7 +329,7 @@ func exportPostgres(c *gin.Context) {
 	args := []string{
 		"--no-password",
 		"-h", dbCfg.Host,
-		"-p", fmt.Sprintf("%d", dbCfg.Port),
+		"-p", strconv.Itoa(dbCfg.Port),
 		"-U", dbCfg.Username,
 		dbCfg.Database,
 	}