TaskManager: without new thread works but blocks REPL

aiorepl (asyncio REPL) works but it's pretty limited

It's probably fine for production, but it means the user has to sys.exit()
in aiorepl before landing on the real interactive REPL, with asyncio tasks stopped.

internal_filesystem/builtin/apps/com.micropythonos.appstore/assets/appstore.py

@@ -130,10 +130,14 @@ class AppStore(Activity):
         print("Downloading icons...")
         for app in self.apps:
             if not self.has_foreground():
-                print(f"App is stopping, aborting icon downloads.")
+                print(f"App is stopping, aborting icon downloads.") # maybe this can continue? but then update_ui_threadsafe is needed
                 break
-            #if not app.icon_data:
-            app.icon_data = await self.download_url(app.icon_url)
+            if not app.icon_data:
+                try:
+                    app.icon_data = await TaskManager.wait_for(self.download_url(app.icon_url), 5) # max 5 seconds per icon
+                except Exception as e:
+                    print(f"Download of {app.icon_url} got exception: {e}")
+                    continue
             if app.icon_data:
                 print("download_icons has icon_data, showing it...")
                 image_icon_widget = None
@@ -146,7 +150,7 @@ class AppStore(Activity):
                         'data_size': len(app.icon_data),
                         'data': app.icon_data
                     })
-                    self.update_ui_threadsafe_if_foreground(image_icon_widget.set_src, image_dsc) # error: 'App' object has no attribute 'image'
+                    self.update_ui_threadsafe_if_foreground(image_icon_widget.set_src, image_dsc) # add update_ui_threadsafe() for background?
         print("Finished downloading icons.")
 
     def show_app_detail(self, app):
@@ -156,7 +160,7 @@ class AppStore(Activity):
 
     async def download_url(self, url):
         print(f"Downloading {url}")
-        #await TaskManager.sleep(1)
+        #await TaskManager.sleep(4) # test slowness
         try:
             async with self.aiohttp_session.get(url) as response:
                 if response.status >= 200 and response.status < 400: