feat(displays): display profiles — docked/undocked switching (item 15a)

nomarchy.displayProfiles: named layouts for the same outputs, each a
list of nomarchy.monitors-style entries. The active profile lives in
the in-flake state (settings.displayProfile) on the night-light
pattern: nomarchy-display-profile apply <name> fires the baked hyprctl
rules instantly and writes the state with --no-switch; the next rebuild
bakes the profile's entries over nomarchy.monitors whole-by-name.
Monitor-rule composition is extracted to pure monitor-rules.nix
(renderer + 3-layer resolve, incl. a disable-guard so a stale menu
resolution pick can't resurrect a profile-disabled panel, and junk
state degrading to base config instead of an eval error) — because a
writeText/toFile state fixture is unreadable at flake-check eval time,
the new checks.display-profiles unit-tests the pure function directly.
Menu: System › Display gains a self-gated "Profiles ›" row (●/○ active
mark, Base layout to clear); commented template example + README row.

Verified: V0 (flake check, forcing the new check's asserts); V1 — a
scratch downstream through lib.mkFlake builds: the generated tool
passes bash -n with correct rules (disable/vrr/float scale), the baked
hyprland.conf shows the exact expected overlay, the menu renders, and
list/usage smoke-test clean. Remains: V3 live switching on a dock
(HARDWARE-QUEUE). Slices b (hotplug auto-switch) + c (workspace
binding) stay in item 15.

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

agent/HARDWARE-QUEUE.md

@@ -140,6 +140,14 @@ QA machine), the **T14s** (webcam case).
       now reflects the real state (the `= true` comparison fix).
       — 2026-07-04 Bernardo: PASS — theme changes committed and the
       toggle self-committed.
+- [ ] **Display profiles, slice a (item 15)** — declare two
+      `nomarchy.displayProfiles` (e.g. docked disables eDP-1 + arranges
+      the externals; undocked re-enables it), `home-update`, then:
+      System › Display › Profiles lists them (● marks active); applying
+      is instant (no rebuild) and survives a relogin (the baked
+      overlay); "Base layout" restores; a menu resolution pick made
+      earlier must NOT re-enable a profile-disabled panel after the
+      next rebuild.
 - [ ] **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