Trying to watch an already watched video will make the video start 15
seconds before the end of the video. This is not very comfortable when
listening to music or watching/listening playlists over and over.
The transcript logic in Invidious was written specifically
as a workaround for captions, and not transcripts as a feature.
This commit genericises the logic a bit as so it can be used for
implementing transcripts within Invidious' API and UI as well.
The most notable change is the added parsing of section headings
when it was previously skipped over in favor of regular lines.
The HTTP::Client created via `make_client` is affected by the
force_resolve configuration option. However, api.invidious.io
does not support ipv6 and as such any request with ipv6 to
api.invidious.io will instead raise.
Directly calling the HTTP::Client will ignore the force_resolve option
allowing requests to go through ipv4 when needed.
Invidious assumes that every playlist will have at least one video
because it needs to check for the `index` key. So if there is no videos
on a playlist, there is no `index` key and Invidious throws
`Index out of bounds`
Videos of a playlist cataloged as podcast are called episodes therefore
Invidious was not able to find `video` in the `text` value inside the
stats array.
Trending music was returning less than 24 videos which was getting
filtered out. Since multiple categories only appears on the default
trending page, we don't need to do that filtering for Music, Gaming or movies.
Closes issue 4596