Function write_codex_config 

pub fn write_codex_config(
    compose: &Compose,
    h: AgentHandle<'_>,
    team_mcp_bin: &str,
) -> Result<()>

Write (or clear) the per-agent Codex config.toml. Mirrors write_subagents_json: the scoped + full render paths both call it so a mcps: edit flows into the agent at the next render. For non-codex agents only the managed config.toml is removed — never the home dir itself, which may hold codex session history worth keeping.