supports chapter option on downloader

src/ytdl_sub/downloaders/downloader.py

@@ -57,6 +57,7 @@ class Downloader(DownloadArchiver, Generic[DownloaderOptionsT, DownloaderEntryT]
 
     supports_download_archive: bool = True
     supports_subtitles: bool = True
+    supports_chapters: bool = True
 
     _extract_entry_num_retries: int = 5
     _extract_entry_retry_wait_sec: int = 3

src/ytdl_sub/downloaders/soundcloud/albums_and_singles.py

@@ -52,6 +52,7 @@ class SoundcloudAlbumsAndSinglesDownloader(
 ):
     downloader_options_type = SoundcloudAlbumsAndSinglesDownloadOptions
     supports_subtitles = False
+    supports_chapters = False
 
     @classmethod
     def ytdl_option_defaults(cls) -> Dict:

src/ytdl_sub/downloaders/youtube/merge_playlist.py

@@ -65,6 +65,7 @@ class YoutubeMergePlaylistDownloader(
     downloader_entry_type = YoutubeVideo
     supports_download_archive = False
     supports_subtitles = False
+    supports_chapters = False
 
     @classmethod
     def ytdl_option_defaults(cls) -> Dict:

src/ytdl_sub/subscriptions/subscription_ytdl_options.py

@@ -105,6 +105,10 @@ class SubscriptionYTDLOptions:
         if not (chapters_plugin := self._get_plugin(ChaptersPlugin)):
             return {}
 
+        if not self._downloader.supports_chapters:
+            # TODO: warn here
+            return {}
+
         return chapters_plugin.ytdl_options()
 
     @property