Add index for channel_id

Channel_id is the main query field for nearly every log related database operation and for some reason it isn't indexed. This should speed up all log related database reliant operations especially on large collections

core/clients.py

@@ -476,6 +476,7 @@ async def setup_indexes(self):
             await coll.create_index(
                 [("messages.content", "text"), ("messages.author.name", "text"), ("key", "text")]
             )
+        await coll.create_index("channel_id", unique=True)
         logger.debug("Successfully configured and verified database indexes.")
 
     async def validate_database_connection(self, *, ssl_retry=True):