Compose 到 Ledger
sequenceDiagram actor U as 用户 participant UI as Compose participant S as SendService participant L as Ledger participant B as Backend participant R as Radio U->>UI: send UI->>S: intent S->>L: Queued S->>B: encode B->>R: enqueue R-->>B: outcome B->>L: Sent/Failed L-->>UI: projection