docs(openspec): archive remove-review-alignment-command

Archives the completed remove-review-alignment-command OpenSpec change now
that /review-alignment and its robot-business-analyst mission are retired
and issue #1084 is closed. Spec deltas were already applied directly to the
living specs during implementation, so archiving used --skip-specs after
verifying all three deltas matched the living specs exactly.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: jabrena