hlsts: prefix playlist segment URLs with ./ so colon-named files resolve

PathEscape leaves ':' alone, so a segment named movie:1.ts parses as
scheme 'movie' and players never resolve it against the playlist URL.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

weed/format/hlsts/hlsts.go

@@ -281,7 +281,7 @@ func renderPlaylist(name string, info *playlistInfo, jwt string) []byte {
 	}
 	for i, durationMs := range info.DurationsMs {
 		fmt.Fprintf(&out, "#EXTINF:%.3f,\n", float64(durationMs)/1000)
-		fmt.Fprintf(&out, "%s?%s=%s&seq=%d%s\n", escapedName, format.ViewParam, FormatName, int64(i)+info.MediaSequence, credential)
+		fmt.Fprintf(&out, "./%s?%s=%s&seq=%d%s\n", escapedName, format.ViewParam, FormatName, int64(i)+info.MediaSequence, credential)
 	}
 	out.WriteString("#EXT-X-ENDLIST\n")
 	return []byte(out.String())

weed/format/hlsts/hlsts_test.go

@@ -121,11 +121,11 @@ func TestViewPlaylist(t *testing.T) {
 #EXT-X-MEDIA-SEQUENCE:0
 #EXT-X-PLAYLIST-TYPE:VOD
 #EXTINF:6.000,
-movie.ts?format.view=hls-ts&seq=0
+./movie.ts?format.view=hls-ts&seq=0
 #EXTINF:6.000,
-movie.ts?format.view=hls-ts&seq=1
+./movie.ts?format.view=hls-ts&seq=1
 #EXTINF:2.500,
-movie.ts?format.view=hls-ts&seq=2
+./movie.ts?format.view=hls-ts&seq=2
 #EXT-X-ENDLIST
 `
 	if string(plan.Body) != want {