Release v4.231.0

Added

• A policy can say require anonymous to let a command or query be called without an identity, so a generated application can expose a public surface such as sign-up or a public verification page. The condition is admitted in ESM v31 as {"kind":"anonymous"}; models without an anonymous policy keep the ESM version they select today. See decision 0103. (#951)
• New diagnostics keep an anonymous policy the whole effective authorization of a command or query: PLAY0804 (combined with another condition in require), PLAY0805 (negated; use authenticated), PLAY0806 (combined with another policy in authorize) and PLAY0807 (under or above another module, feature, command or query gate). (#951)
• Specifications of a command or query whose only authorization is an anonymous policy may omit given caller. (#951)
• The Invoicing sample gains a PublicVerification module that lets anyone confirm an invoice number was issued. (#951)