Change Channel to Source (#12)

* Ensure channel detail lookup doesn't download the video - oops

* Ran the needful migrations for replacing channels with sources

* got media source test back working

* channel tasks test

* Media indexing worker test

* media tests

* Got all tests working except controller tests

* got all tests working

* Renamed Channel struct to Source

* renamed ChannelTasks

* More renaming; renamed channel details module

* Removed Channel yt-dlp module, instead throwing things in the VideoCollection module

* Renamed what looks like the last of the outstanding data

lib/pinchflat/media_client/video_downloader.ex

@@ -25,8 +25,8 @@ defmodule Pinchflat.MediaClient.VideoDownloader do
   Returns {:ok, %MediaItem{}} | {:error, any, ...any}
   """
   def download_for_media_item(%MediaItem{} = media_item, backend \\ :yt_dlp) do
-    item_with_preloads = Repo.preload(media_item, [:metadata, channel: :media_profile])
-    media_profile = item_with_preloads.channel.media_profile
+    item_with_preloads = Repo.preload(media_item, [:metadata, source: :media_profile])
+    media_profile = item_with_preloads.source.media_profile
 
     case download_for_media_profile(media_item.media_id, media_profile, backend) do
       {:ok, parsed_json} ->