implement-dev-plan — From Approved Plan to Reviewed, Uncommitted Implementation

Core Principle

The plan already made the decisions: which files, which tasks in which order, which interfaces, and which test proves which requirement. Implementation is where those decisions meet reality, and reality pushes back — a signature does not fit, a test name is wrong for the framework, a spec criterion turns out ambiguous once the code exists. This workflow exists so that every push-back is seen, decided by the user, and recorded, instead of being absorbed silently into code that no longer matches its plan. Three habits make that possible: nothing is trusted that the main agent did not run itself, nothing changes in the plan except checkboxes and Change Log rows, and nothing is committed — the user reviews the diff and decides what enters history.

The output is uncommitted code plus three documents: