try..

app.py

@@ -1,9 +1,9 @@
 import gradio as gr 
-from detection import app
+from detection import app as detector
 from recognition import app_easyocr
 
 def recognize(img_arr):
-    detections = app.detect(img_arr)
+    detections = detector.detect(img_arr)
     return img_arr, detections
 
 

detection/app.py

@@ -1,5 +1,4 @@
 import os
-import gradio as gr
 import argparse
 import time
 from pathlib import Path