Misc refactors 2024-03-14 (#89)

* Adds method to improve cleanup of empty directories

* resolved bug where source metadata worker could call itself in an infinite loop

* Refactored file deletion for media items

* Removed useless filesystem data worker

* Updated task listing fns to take a record directly

* Refactored the way I call workers

* Improved some tests

test/pinchflat/sources_test.exs

@@ -508,70 +508,6 @@ defmodule Pinchflat.SourcesTest do
     end
   end
 
-  describe "maybe_change_source_from_url/2" do
-    test "it returns a changeset" do
-      stub(YtDlpRunnerMock, :run, &channel_mock/3)
-      source = source_fixture()
-
-      assert %Ecto.Changeset{} = Sources.maybe_change_source_from_url(source, %{})
-    end
-
-    test "it does not fetch source details if the original_url isn't in the changeset" do
-      expect(YtDlpRunnerMock, :run, 0, &channel_mock/3)
-
-      changeset = Sources.maybe_change_source_from_url(%Source{}, %{name: "some updated name"})
-
-      assert %Ecto.Changeset{} = changeset
-    end
-
-    test "it fetches source details if the original_url is in the changeset" do
-      expect(YtDlpRunnerMock, :run, &channel_mock/3)
-
-      changeset =
-        Sources.maybe_change_source_from_url(%Source{}, %{
-          original_url: "https://www.youtube.com/channel/abc123"
-        })
-
-      assert %Ecto.Changeset{} = changeset
-    end
-
-    test "it adds source details to the changeset, keeping the orignal details" do
-      expect(YtDlpRunnerMock, :run, &channel_mock/3)
-
-      media_profile = media_profile_fixture()
-      media_profile_id = media_profile.id
-
-      changeset =
-        Sources.maybe_change_source_from_url(%Source{}, %{
-          original_url: "https://www.youtube.com/channel/abc123",
-          media_profile_id: media_profile.id
-        })
-
-      assert %Ecto.Changeset{} = changeset
-      assert String.starts_with?(changeset.changes.collection_id, "some_channel_id_")
-
-      assert %{
-               collection_name: "some channel name",
-               media_profile_id: ^media_profile_id,
-               original_url: "https://www.youtube.com/channel/abc123"
-             } = changeset.changes
-    end
-
-    test "it adds an error to the changeset if the runner fails" do
-      expect(YtDlpRunnerMock, :run, 1, fn _url, _opts, _ot ->
-        {:error, "some error", 1}
-      end)
-
-      changeset =
-        Sources.maybe_change_source_from_url(%Source{}, %{
-          original_url: "https://www.youtube.com/channel/abc123"
-        })
-
-      assert %Ecto.Changeset{} = changeset
-      assert errors_on(changeset).original_url == ["could not fetch source details from URL"]
-    end
-  end
-
   defp playlist_mock(_url, _opts, _ot) do
     {
       :ok,