Retry With Backoff

Execute explicit retry policy: max 3, base 2s, max 30s, full jitter, 60s total budget, respects `Retry-After`. USE WHEN: `error-recovery-strategy` classified error as `transient` and chose `retry`, HTTP 429 with `Retry-After` header, network timeout/refused/reset, queue/lock/eventually-consistent read returned stale, user said "重试" / "retry" / "再试" / "等一下" / "等几秒" / "backoff" / "exponential" / "rate limit" / "429" / "限流". TRIGGER PHRASES: "重试", "retry", "再试", "等一下", "等几秒", "backoff", "exponential", "rate limit", "429", "Retry-After", "throttled", "限流", "busy", "服务忙". SKIP WHEN: error is `deterministic` (won't change on retry), error is `unknown` (escalate to ask-user), wo…