pub fn write_subagents_json(compose: &Compose, h: AgentHandle<'_>) -> Result<()>Expand description
Write (or clear) the per-agent --agents JSON file. Mirrors
write_role_prompt_concat: the scoped + full render paths both call
it so a subagents: edit flows into the agent at the next render. When
the agent declares no sub-agents (or isn’t claude-code) the file is
removed if present, so a stale --agents set never lingers across a
reload that dropped them.