Support multiparty public deals

docs/BRIBE_CONTROLS.md

@@ -23,8 +23,8 @@ places paid bribes in front of the recipient's shield until the next Mentat Paus
 Chat messages and verbal promises do not themselves transfer spice. Emperor
 gifts to allies remain a separate power.
 
-The separate [public deal record](PUBLIC_DEALS.md) can capture a two-human
-offer, acceptance and mutual release. Its written terms do not automatically
+The separate [public deal record](PUBLIC_DEALS.md) can capture a two-to-six-human
+offer, unanimous acceptance and mutual release. Its written terms do not automatically
 transfer spice or enforce future promises; use this native action to pay.
 
 The server derives the owner's limits from existing uncommitted spice, excluding