docs: close §E approval-ergonomics re-audit (move to RETRO)

The re-audit passed and its one gap — line-only diff-viewer scroll — was
fixed in db27b34. Cut the BACKLOG §E item and record the result + the
diff-viewer paging commit in RETRO 2026-06-22.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

RETRO.md

@@ -36,10 +36,15 @@ test` green and rendered via `cmd/preview` before commit:
 | `6a06f2e` | Inline action rows in the OUTPUT transcript (tool results / approvals / writes / grants as `RouterEntry` role `action`, interleaved by arrival). |
 | `f14a83c` | Drop the inline tool-*start* rows (they doubled up with the result rows). |
 | `531910d` | Transcript free-scroll (`PgUp/PgDn`, `^u/^d`, `esc` snaps to tail-follow; clamped via `outputViewport()`/`buildTranscriptRows`, 2 tests) + help overlay (`?`) + event-inspector `/` filter. |
+| `db27b34` | Page-scroll the `^x` diff/preview/command fullscreen viewer (`↑↓` line, `PgUp/PgDn` page, `^u/^d` half, `g/G` ends; `scrollDiff()` clamp, 2 tests) + advertise it in the modal hint and the `?` help overlay. Closes the §E approval-ergonomics re-audit. |
 
-These are mostly deterministic render/UX changes (verifiable by `go test` + `cmd/preview`); the
-only remaining live look is the §E approval-ergonomics re-audit noted in BACKLOG (the band gained
-the grant scope-picker + action rows since `d5afcd3`).
+These are mostly deterministic render/UX changes (verifiable by `go test` + `cmd/preview`).
+
+**§E approval-ergonomics re-audit — DONE (`db27b34`).** Re-checked the band after it gained the
+grant scope-picker (`A`) and inline action rows: the spec still holds — single-key `y/n/e` for
+T0–T2, mandatory second-key confirm for T3+ (`HighTier`), navigable queue with an `i/n` indicator,
+docked band never modal-stacks. All covered green by `approval_test.go`. The one gap was the diff
+viewer scrolling one line at a time; `db27b34` adds paging. Item moved out of BACKLOG.
 
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