fix issue with no scan

Dockerfile.backend

@@ -7,6 +7,6 @@ COPY --chown=reflex --from=gitea.pb42.de/matthias/reflex-ipad:builder /app /app
 COPY --chown=reflex deploy/* .
 RUN chown reflex:reflex /app
 USER reflex
-ENV PATH="/app/.venv/bin:$PATH" API_URL=$API_URL
+ENV PATH="/app/.venv/bin:$PATH" API_URL=$API_URL PYTHONUNBUFFERED=TRUE
 
 CMD reflex db migrate && reflex run --env dev --backend-only

reflex_ipad/pages/medicine.py

@@ -36,6 +36,8 @@ class NewMedicineState(rx.State):
             statement = select(Scan).order_by(Scan.timestamp.desc()).limit(1)
             results = session.exec(statement)
             self.last_scan = results.first()
+            if self.last_scan is None:
+                return
             if self.last_scan.timestamp > self.lastupdatetime:
                 self.last_scan_uuid = self.last_scan.uuid
                 if not self.show_med_add_form: