[FEATURE]: Subagent rate limit hit should surface message like main agent #10724

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Describe the enhancement you want to request

When OpenCode hits a rate limit on the primary agent, it correctly displays a message indicating that the request was rate limited and shows the retry time. This works both when a prompt is actively executing and when the request is made immediately (see attached screenshot).

However, when a subagent hits a rate limit, no similar feedback is shown to the user. The request appears to silently fail or stall, and there’s no indication of what happened or when it can retry.