new apps.lyric.authenticate model PasswordlessAuthenticationBackend and authenticate() function help determine Token authenticity, login to existing accounts, or create new ones; associated .tests.test_authentication class asserts this functionality; apps.lyric.models & .tests.models now handles token uid instead of id, completing the transition away from email-as-pk

src/apps/lyric/models.py

@@ -3,7 +3,7 @@ from django.db import models
 
 class Token(models.Model):
     email = models.EmailField()
-    uid = models.UUIDField(default=uuid.uuid4)
+    uid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
 
 class User(models.Model):
     id = models.BigAutoField(primary_key=True)