docs(hardware): round 6 settles 4 of 5 counts; headphones still untested

Bernardo's round 6 report plus the keyboard result confirms on hardware:
wallpaper on the external, automatic dock mode, audio reaching the
monitor, and the external keyboard prompting exactly once (was four).

That leaves headphone jack-follow as the only count from rounds 4-6 never
tested at all, so it gets its own entry rather than staying buried in a
list of settled ones. Fold it into the round 7 session — the dock is
already in hand and the two checks don't interfere.

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

agent/JOURNAL.md

@@ -43,8 +43,10 @@ Template:
   collides the two. The fix itself is **V3 pending**; comment added at
   tools/monitor-fallback.nix so a reader doesn't mistake a pass for coverage.
 - **Pending:** V3 → HARDWARE-QUEUE round 7 (unplug ≥5×; old failure was only
-  ~2 in 3). Round 5/6's keyboard-prompt + headphone-jack counts were never
-  reported either way — split into their own entry, still unverified.
+  ~2 in 3). Rounds 4–6 opened 5 counts: 4 are now confirmed fixed on hardware
+  (wallpaper, auto-dock, monitor audio, keyboard prompting once — Bernardo),
+  the undock is this commit, and **headphone jack-follow is still untested** —
+  now its own entry, to fold into the round 7 session.
 - **Next suggestion:** wait on round 7 before touching the dock path again.
 
 ## 2026-07-13 — #99 live-seed git-init; theme-switch failure filed as #113 (this commit)