Rename the import package app to fluksio

A wheel whose top-level module is `app` collides with anything else in a
user's venv, so the package that is about to be published takes the name
it is published under. Only the Python package moves; the repo, the
Docker WORKDIR and the compose project keep theirs.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

backend/tests/api/routes/test_users.py

@@ -4,10 +4,10 @@ from unittest.mock import patch
 from fastapi.testclient import TestClient
 from sqlmodel import Session, select
 
-from app import crud
-from app.core.config import settings
-from app.core.security import verify_password
-from app.models import User, UserCreate
+from fluksio import crud
+from fluksio.core.config import settings
+from fluksio.core.security import verify_password
+from fluksio.models import User, UserCreate
 from tests.utils.user import create_random_user
 from tests.utils.utils import random_email, random_lower_string
 
@@ -38,9 +38,9 @@ def test_create_user_new_email(
     client: TestClient, superuser_token_headers: dict[str, str], db: Session
 ) -> None:
     with (
-        patch("app.utils.send_email", return_value=None),
-        patch("app.core.config.settings.SMTP_HOST", "smtp.example.com"),
-        patch("app.core.config.settings.SMTP_USER", "admin@example.com"),
+        patch("fluksio.utils.send_email", return_value=None),
+        patch("fluksio.core.config.settings.SMTP_HOST", "smtp.example.com"),
+        patch("fluksio.core.config.settings.SMTP_USER", "admin@example.com"),
     ):
         username = random_email()
         password = random_lower_string()