Add beamtime relationships and enhance sample handling

This commit adds relationships to link Pucks and Samples to Beamtime in the models, enabling better data association. Includes changes to assign beamtime IDs during data generation and updates in API response models for improved data loading. Removed redundant code in testfunctions.ipynb to clean up the notebook.

backend/main.py

@@ -168,8 +168,8 @@ async def lifespan(app: FastAPI):
             load_slots_data(db)
         else:  # dev or test environments
             print(f"{environment.capitalize()} environment: Regenerating database.")
-            # Base.metadata.drop_all(bind=engine)
-            # Base.metadata.create_all(bind=engine)
+            Base.metadata.drop_all(bind=engine)
+            Base.metadata.create_all(bind=engine)
             # from sqlalchemy.engine import reflection
             # from app.models import ExperimentParameters  # adjust the import as needed
             # inspector = reflection.Inspector.from_engine(engine)