refactor(lyrics): move test-only parseTTML/parseSRT wrappers to test files

These zero-arg wrappers (defaulting lang to "xxx") had no production callers
after the consolidation — only the format tests used them. Move each beside
its tests so the production files carry no test-only code.

model/lyrics_srt.go

@@ -14,10 +14,6 @@ var (
 	srtBlockSeparatorRegex = regexp.MustCompile(`\n\s*\n`)
 )
 
-func parseSRT(contents []byte) (LyricList, error) {
-	return parseSRTWithLanguage("xxx", contents)
-}
-
 func parseSRTWithLanguage(language string, contents []byte) (LyricList, error) {
 	raw := strings.ReplaceAll(string(contents), "\r\n", "\n")
 	raw = strings.ReplaceAll(raw, "\r", "\n")

model/lyrics_srt_test.go

@@ -5,6 +5,11 @@ import (
 	. "github.com/onsi/gomega"
 )
 
+// parseSRT parses with the default placeholder language, for test ergonomics.
+func parseSRT(contents []byte) (LyricList, error) {
+	return parseSRTWithLanguage("xxx", contents)
+}
+
 var _ = Describe("parseSRT", func() {
 	It("parses SRT blocks with the default language", func() {
 		content := []byte("1\n00:00:01,000 --> 00:00:02,000\nFirst subtitle\n\n2\n00:00:03,000 --> 00:00:04,000\nSecond subtitle")

model/lyrics_ttml.go

@@ -102,10 +102,6 @@ type ttmlParser struct {
 	metadataSeq int
 }
 
-func parseTTML(contents []byte) (LyricList, error) {
-	return parseTTMLWithDefaultLang("xxx", contents)
-}
-
 func isTTMLDocument(text string) bool {
 	decoder := xml.NewDecoder(strings.NewReader(strings.TrimSpace(text)))
 	for {

model/lyrics_ttml_test.go

@@ -5,6 +5,11 @@ import (
 	. "github.com/onsi/gomega"
 )
 
+// parseTTML parses with the default placeholder language, for test ergonomics.
+func parseTTML(contents []byte) (LyricList, error) {
+	return parseTTMLWithDefaultLang("xxx", contents)
+}
+
 var _ = Describe("parseTTML", func() {
 	Describe("Multi-language and timing", func() {
 		It("should parse multiple language divs with inherited offsets and frame/tick timing", func() {