Fix OSC8 hyperlinks mangled when URL contains unicode

Fix #4707

src/algo/indexbyte2_arm64.go

@@ -7,7 +7,7 @@ package algo
 // to search for both bytes in a single pass.
 //
 //go:noescape
-func indexByteTwo(s []byte, b1, b2 byte) int
+func IndexByteTwo(s []byte, b1, b2 byte) int
 
 // lastIndexByteTwo returns the index of the last occurrence of b1 or b2 in s,
 // or -1 if neither is present. Implemented in assembly using ARM64 NEON,