protection against bridge enumeration
Add protection against bridge enumeration, so if an attacker wants to get the full list of bridges it can't easly do that.
Let's provide a salmon like mechanism:
- there are two pools of bridges (A, B)
- any old enough account can get bridges from pool A. Or if old is not something that exist in whatsapp we can enable some accounts manually for that.
- any account after X days of using bridges from pool A will be moved to use bridges from pool B.
- every account using bridges from pool B can invite Y number of accounts every Z days to use bridges from pool B.