modernize 37→5（-32）：interface{}→any、内置 max/min、slices/maps 辅助、strings.Cut/SplitSeq、strings.Builder（修复 mail.go O(n²) 拼接）。逐 hunk 核对语义等价；omitzero 冲突修复被自动跳过（wire 格式不变）；手动清 4 处遗留 sort import + 2 处 QF1012。

Result: {"status":"keep","total_issues":74,"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":18,"golint_prealloc":3,"golint_recvcheck":7,"golint_usestdlibvars":3,"golint_wastedassign":7,"golint_total":73,"eslint_problems":1,"eslint_errors":0,"eslint_warnings":1,"tsc_errors":0,"measure_s":38}

internal/apps/openflare/option/openresty_validators.go

@@ -189,7 +189,7 @@ func validateOpenRestyCacheUseStale(key, trimmed string) error {
 		"http_500": {}, "http_502": {}, "http_503": {}, "http_504": {},
 		"http_403": {}, "http_404": {}, "http_429": {}, "off": {},
 	}
-	for _, token := range strings.Fields(trimmed) {
+	for token := range strings.FieldsSeq(trimmed) {
 		if _, ok := allowedTokens[token]; !ok {
 			return fmt.Errorf("%s 包含不支持的值 %q", key, token)
 		}