flow-implementlisted

## Prerequisites - An approved plan exists for this project: `ls -t "$(scratch-dir.sh)"/plan-\*.md | head -1`. If none, run /flow-plan first. - If $ARGUMENTS specifies a step or range, implement only those. Otherwise implement the next unchecked step. ## Procedure 1. Get the scratch directory: `!`scratch-dir.sh``. Read the most recent plan: `ls -t "$(scratch-dir.sh)"/plan-\*.md | head -1`. Identify the step to implement. 2. Confirm the files involved still match the plan. - If drift (file moved, API changed, dependency bump): - Stop. - Do not modify code. - Identify the mismatch. - Report with a proposal: revise the plan, escalate to the user, or pivot to a smaller scope. - If a step calls for writing content the plan describes as verbatim but does not actually inline (references a payload by name only): stop and report the gap rather than reconstructing the content from memory or this conversation's earlier history - the plan file is the only source this step may rely on. 3. Load the patterns skill for the stack if the change is stack-specific. - You may delegate noisy sub-work (broad code exploration, running checks) to the scout or checker agent to keep this context clean, but every phase-boundary stop stays in the main conversation. 4. Make the changes. One step at a time. After each file: - Match existing style, naming, and patterns. Read a nearby file first if unsure. - Do not refactor unrelated code. - Do not upgrade or add depe