feat(displays): hotplug auto-switch for display profiles (item 15b)

nomarchy-display-profile gains `match <outputs>`: an exact set match
wins, else the largest profile whose named outputs are all connected;
any tie prints nothing — the watcher must never flap between ambiguous
layouts. nomarchy-display-profile-watch (exec-once when profiles are
declared, the keyboard-watcher poll pattern — session units race
Hyprland IPC on relogin) reacts to output-set CHANGES only, reads
settings.displayProfileAuto from the live state each time (the menu's
new Auto-switch row toggles it instantly, no rebuild), and applies via
the tool — so an auto-pick persists a concrete profile that the next
rebuild bakes. A separate boolean rather than an "auto" pseudo-profile
for exactly that bake semantics.

Verified: V0 (flake check); V1 — a scratch 4-profile downstream builds;
tool + watcher pass bash -n; the match matrix exercised end-to-end:
three exact picks, an unambiguous-superset pick, a tie -> none, a
no-fit -> none; the watcher is exec-once'd in the rendered config; the
menu renders the Auto-switch row. Remains: V3 real dock/undock
(HARDWARE-QUEUE, rides the slice-a entry). Slice c (workspace binding)
stays, tagged optional.

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

agent/HARDWARE-QUEUE.md

@@ -148,6 +148,11 @@ QA machine), the **T14s** (webcam case).
       overlay); "Base layout" restores; a menu resolution pick made
       earlier must NOT re-enable a profile-disabled panel after the
       next rebuild.
+- [ ] **Display profiles auto-switch, slice b (item 15)** — same setup,
+      then menu › Profiles › Auto-switch on: plugging the dock/monitor
+      applies the matching profile within ~3s (toast names it);
+      unplugging switches back; Auto-switch off stops that; with two
+      profiles naming the same outputs, no flapping (ties do nothing).
 - [ ] **Color picker (item 13, final slice)** — SUPER+CTRL+P (or Tools ›
       Color picker): hyprpicker's zoom loupe appears; click a pixel →
       toast shows the hex and `wl-paste` yields it; Esc cancels with no