Limit amount of messages from user per day if reputation (karma) is less than -10

* 64 messages per day in chat if karma < -10 and karma >= -20
* 32 messages per day in chat if karma < -20 and karma >= -40
* 16 messages per day in chat if karma < -40 and karma >= -80
* 8 messages per day in chat if karma < -80 and karma >= -160
* 4 messages per day in chat if karma < -160 and karma >= -320
* 2 messages per day in chat if karma < -320 and karma >= -640
* 1 messages per day in chat if karma < -640 and karma >= -1280
* Read only mode if karma < -1280

No files, tests, or entry points are named. Search the bot's chat-message handling and karma checks first, then verify that each listed karma range enforces its daily message limit and that karma below -1280 produces read-only behavior.

Written by the indexing model from the issue text.