fix(userbot): drop stale media sessions and survive download timeouts

backend/src/userbot/modules/jobs/handlers/fetch_custom_emoji.py

@@ -1,8 +1,7 @@
-from io import BytesIO
-
 from pyrogram.types import Sticker
 
 from userbot.modules.custom_emoji.repository import is_downloaded, upsert_downloaded
+from userbot.modules.download import download_bytes
 from userbot.modules.jobs.context import JobContext
 from userbot.modules.jobs.registry import register
 
@@ -30,10 +29,9 @@ async def fetch_custom_emoji(ctx: JobContext) -> None:
     if not stickers:
         return
     sticker = stickers[0]
-    buffer = await client.download_media(sticker.file_id, in_memory=True)
-    if not isinstance(buffer, BytesIO):
+    data = await download_bytes(client, sticker.file_id)
+    if data is None:
         return
-    data = buffer.getvalue()
     storage_key = capture.storage.put(data)
     await upsert_downloaded(
         ctx.pool,