add registration page with nickname/phone fields and fix lateinit crashes

sentence_api/main.py

@@ -165,7 +165,8 @@ def create_app(
         user = video_repository.create_user(
             username=payload.username,
             password=payload.password,
-            nickname=payload.username,
+            nickname=payload.nickname or payload.username,
+            phone=payload.phone,
         )
         if user is None:
             raise HTTPException(status_code=409, detail="Username is already taken.")