plan mode for planning idea and execute with todo list

What feature would you like to see?

I usually start Codex session with an mode "planning".

1. codex create DEVELOP-make-game.md with my request.
2. I review the develop md file, or modify any detail to fit my idea.
3. codex create TODO-make-game.md with plan.
4. codex coding, review and check the TODO list file.

I review the DEVELOP-make-game.md, if any request is everything fit my request.
Than create the TODO-make-game.md by asking codex to generate with my favorite programing lang, package, data structure.
Use Planning mode by create DEVELOP-plan-name.md with TODO-plan-name.md, and finish the request.

Mayby codex can automaticly start the deveop+todo mode with any request by default for with option to switch.

Additional information

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