Execute analyzed PR plans

Read ../_shared/base-green.md, ../_shared/validation-gate.md, ../_shared/merge-gates.md, ../_shared/protected-surfaces.md and ../_shared/credit-preservation.md before execution. Their authority and evidence boundaries apply throughout; no throughput exception waives required checks.

1. Reconcile and choose

Refresh live PR states/heads/bases, worktree ownership, freeze state and existing plans under _tasks/pipeline/prs/1-analyzed/. Preserve other sessions' claims. No plan means return to review; an explicit owner request for inline review may authorize a bounded mini-analysis, not skip validation or merge authorization.