fix: stop autoplay after final episode

internal/templates/watch.templ

@@ -14,6 +14,7 @@ type WatchPageData struct {
 	MalID          int
 	Title          string
 	CurrentEpisode string
+	TotalEpisodes  int
 	StartTimeSeconds float64
 	CurrentStatus  string
 	InitialMode    string
@@ -196,6 +197,7 @@ templ VideoPlayer(data WatchPageData) {
 	<div
 		class="flex flex-col gap-4 w-full"
 		data-mal-id={ fmt.Sprintf("%d", data.MalID) }
+		data-total-episodes={ fmt.Sprintf("%d", data.TotalEpisodes) }
 		data-video-player
 		data-stream-url="/watch/proxy/stream"
 		data-current-episode={ data.CurrentEpisode }