Added thumnails.

src/rupload/app.py

@@ -271,10 +271,7 @@ async def handle_upload(request: web.Request):
 async def handle_thumbnail(request: web.Request):
     path = request.match_info["path"]
     
-    safe_path = pathlib.Path(request.app.upload_path).joinpath(path)
-    
-    if not safe_path.exists():
-        return web.Response(status=404, text="File not found.")
+    safe_path = pathlib.Path(path)
     
     if not safe_path.is_file():
         return web.Response(status=400, text="Invalid file type.")