* fix(backend): return mcp message_task once dispatched, not after target turn ends
The MCP message_task_kandev tool was synchronously waiting for the target
session's entire turn to complete before returning, even though its
description advertises a fast dispatch status. For idle target sessions,
the call would hang for the full duration of the agent's response (with
no upper bound — waitForPromptDone has no timeout).
Threads a dispatchOnly flag from the MCP handler down through
PromptTask → executor.Prompt → PromptAgent → SendPrompt. When set,
SendPrompt returns once agentctl.Prompt accepts the prompt instead of
blocking on the agent's complete event. Stale completion signals from
prior dispatch-only prompts are drained at the start of SendPrompt so
they don't poison the next waiting call.
* fix: address PR review feedback
- Replace time.Sleep with channel-based wait for WS connection in new
SendPrompt tests, per CLAUDE.md (channel sync over time.Sleep for
non-subprocess tests).
- Drop redundant Warn that logged the remapped sentinel after the
original error was already logged by the preceding Warn.
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Co-authored-by: Kandev Agent <agent@kandev.dev>
João Salavisa
96c68a0af9