docs: only the user's explicit approval accepts or merges an ADR

The user's ruling: "An ADR isn't approved until I say it is." CI, the
reviews and the adversarial review stay required as gates, but none of
them is approval. SKILL.md's "not on a review" pointer is reworded to
match.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VdfEGXA7aJ6ftMsCc9PJze

AGENTS.md

@@ -259,17 +259,20 @@ meaningful.
 
 ### ADR pull requests
 
-An ADR (`context/adr/`) merges on the user's approval, **in addition to** green
-CI, every review answered, and a passing adversarial review ("Shipping a
-wave"). The approval is an extra gate. It replaces none of the others. The
-steps, modelled on PR #122 (ADR 004):
+**Only the user's explicit approval accepts an ADR (`context/adr/`), and only
+it lets an ADR PR merge.** "An ADR isn't approved until I say it is" (the
+user). Green CI, every review answered and a passing adversarial review
+("Shipping a wave") are still required. They are gates, never approval: an ADR
+PR that passes all of them is still unapproved and does not merge. The steps,
+modelled on PR #122 (ADR 004):
 
 1. The PR proposes the ADR with its **open questions numbered**.
 2. The user answers them on the PR.
 3. The answers are folded into the ADR, in a section headed **"What the user
    decided"**.
 4. The PR merges only after the user comments **"Approved"**, and only while
-   the other gates still hold. "Read the PR's reviews before merging it" still
+   the gates above still hold. Nobody else's comment or review stands in for
+   it. "Read the PR's reviews before merging it" still
    applies after the approval. On #122 the user's own review landed as the PR
    merged.