Implement code based on the change artifacts. Supports three modes: - Gherkin-driven (default): feature files drive implementation and testing - Proposal-driven : when gherkin is skipped (technical changes), proposal drives testing - Fix-from-verify : the open findings in are the task list (see step 4) <decision boundary Use for: - Implementing code for a Beat change that has spec artifacts (gherkin or proposal) done - TDD implementation driven by feature files or proposal risk points - Resuming implementation of a partially completed change - Fixing the open findings of the last run ("fix th…