Implement Feature (SAM Workflow Execution)

This workflow continues from add-new-feature. It executes tasks from the selected provider until complete or blocked.

<plan_ref>$ARGUMENTS</plan_ref>

Load dh:dh-cli-usage before using <sam_cli/> or <dh_scripts/> below.

Where task state lives: every command that moves a task — ready, dispatch, settle, read, accept, reclaim, state, status — runs through the <sam_cli/> command above, against the work ledger. The sam_plan and sam_task MCP tools answer from the content store, which holds the plan's authored content and none of the attempt, lease, or outcome state this loop turns on, so this workflow reaches task state through the CLI.