Compatibility Issue: OpenProse assumes blocking subagent semantics, incompatible with OpenClaw's async model

[helianbobo]

OpenProse currently assumes a blocking subagent execution model (Claude Code's Task tool), which makes it incompatible with platforms like OpenClaw that use async non-blocking subagent spawning (sessions_spawn).

Specific Incompatibilities

1. Session Statement Semantics

let research = session: researcher
  prompt: "Research X"
# VM waits here until subagent writes research.md
session: writer
  context: research  # Depends on research being ready

OpenClaw Reality:

{ status: "accepted", runId: "...", childSessionKey: "..." }
// VM has no way to wait for completion