Add MusicLibrary.Notes contex functions

lib/music_library/notes.ex

@@ -0,0 +1,24 @@
+defmodule MusicLibrary.Notes do
+  alias MusicLibrary.Notes.Note
+  alias MusicLibrary.Repo
+
+  def get_note(entity, musicbrainz_id) do
+    Repo.get_by(Note, entity: entity, musicbrainz_id: musicbrainz_id)
+  end
+
+  def create_note(note, attrs) do
+    note
+    |> Note.changeset(attrs)
+    |> Repo.insert()
+  end
+
+  def update_note(note, attrs) do
+    note
+    |> Note.changeset(attrs)
+    |> Repo.update()
+  end
+
+  def change_note(note, attrs) do
+    Note.changeset(note, attrs)
+  end
+end