refactor: clean up unused imports and improve code organization

src/logic/threads_copy.py

@@ -1,6 +1,4 @@
-import os
 import sqlite3
-import threading
 import time
 
 from PyQt6.QtCore import QThread, pyqtSignal
@@ -8,7 +6,6 @@ from PyQt6.QtCore import QThread, pyqtSignal
 from src.backend.database import Database
 from src.logic.log import MyLogger
 from src.logic.webrequest import BibTextTransformer, WebRequest
-from src.transformers import RDS_AVAIL_DATA
 
 # from icecream import ic
 
@@ -213,7 +210,6 @@ class AutoAdder(QThread):
 
 
 class MockAvailCheck:
-
     def __init__(
         self, links: list = None, appnumber: int = None, parent=None, books=list[dict]
     ):