The SDKs read retryable

The SDKs read retryable (in the same versions). They retry an answer that says retryable: true after its Retry-After, and never one that says false. A create, wake or restart waits out room and the account's limits for its own wait for room (two minutes by default; 0 returns at once), and a fork returns them at once. An answer whose wait is over a minute (a daily cap) is returned at once, with retryAfterMs. The Go, Ruby and Java SDKs now also resend a call refused guest_busy, busy or rate_limited until its deadline, as JavaScript and Python do. The CLI's --json errors carry retryable and retryAfterMs.