beevibe-pre-task-setup

Cold-start git workspace setup for a fresh beevibe task. Use at the start of a session whose intent has a <task> block but NO <context type="revision"> or <context type="post_escalation"> block — i.e. the first dispatch of this task. Checks for an existing repo clone, pulls the base branch if present (clone if missing), prunes any per-task worktrees from earlier tasks whose work has already landed on the default…