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/fluksio/initial_data.py

@@ -0,0 +1,23 @@
+import logging
+
+from sqlmodel import Session
+
+from fluksio.core.db import engine, init_db
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+
+def init() -> None:
+    with Session(engine) as session:
+        init_db(session)
+
+
+def main() -> None:
+    logger.info("Creating initial data")
+    init()
+    logger.info("Initial data created")
+
+
+if __name__ == "__main__":
+    main()