Identity Sovereignty

See moves README for orientation. This is the eighth design move.

Users own their identity, portable between instances. Pseudonymity is permitted; one-human-one-account verification (proof-of-personhood) at registration without revealing the underlying identity.

• Why: Lord-controlled identity is a vector for vassalage; the alternative needs to make exit cheap.
• Cost: Proof-of-personhood schemes are immature; sybil resistance without identity disclosure is technically hard.