Break code change into steps

[johnsonr]

Requires ability to add additional planning steps, or possibly a subprocess step that iterates

Could use critique etc. also

[johnsonr]

This can be built in a general way on the blackboard, with a checklist condition, or pulling something from the blackboard.

Blackboard objects must not be removed and must remain immutable, however.

[johnsonr]

Or a checklist type where the LLM is instructed as to the current step.