AskUser tool in Droid CLI fails to proceed under Agent Client Protocol (ACP) sessions

[thezzisu]

When using the AskUser tool within a Droid CLI session over ACP, the session hangs after the initial tool invocation. Only a single session/update notification is triggered with the following payload:

{
  "jsonrpc": "2.0",
  "method": "session/update",
  "params": {
    "sessionId": "6e55f85f-b15d-40cd-b312-abf6392f418d",
    "update": {
      "sessionUpdate": "tool_call",
      "toolCallId": "toolu_bdrk_01HfQsZHng6Si5KxDa8TYS8n",
      "title": "AskUser",
      "kind": "other",
      "status": "pending",
      "rawInput": {
        "questionnaire": "..."
      }
    }
  }
}

The issue:
After this message, the session becomes unresponsive:

No subsequent permission request events are fired.

No tool status updates are received.

The Prompt Turn never completes, resulting in a session deadlock/hang.

The full ACP JSON-RPC log is attached:
transcript-019cb3a1-3acb-7ee3-bcd6-da35ec446f48.json