The backend currently initializes tables on startup with `create_all()`. We already have Alembic in the repo, so schema management should move fully to migrations.

[bme2003]

Why

create_all() can hide schema drift and makes production boot behavior less predictable.

Proposed Change

• Remove init_db() / create_all() from FastAPI startup
• Document migration-first startup flow
• Ensure local development still works cleanly with alembic upgrade head

Acceptance Criteria

• App starts without calling create_all()
• README reflects the new boot flow
• Existing schema can be created through Alembic only

[IlyasFardaouix]

I think the issue here is that run_migrations_online() is still calling context.run_migrations() which will create the tables. To fix this, you should remove the context.run_migrations() call and instead rely on Alembic to create the tables during the migration process.