implementlisted

Implement the work described by the user in the PRD or issues. Use /tdd where possible, at pre-agreed seams. Run typechecking regularly, single test files regularly, and the full test suite once at the end. Before /code-review, run /simplify over the changed code. <!-- simplify is deliberately not wired into the unattended build path (BUILD_PROMPT): unattended builds are budget-bound and simplify applies edits outside the diff. --> Once done, use /code-review to review the work. Commit your work to the current branch.