feat(hyprland): launch-or-focus binds (item 17)

nomarchy.launchOrFocus (opt-in, commented template example): each
entry gives a key that FOCUSES the app's existing window
(case-insensitive class match via jq + a "(?i)" focuswindow regex) or
launches it when none is open. One shared nomarchy-focus-or-launch
script; a bind whose command was removed from the suite fires a
"not installed" toast instead of failing silently. The same entries
render into the SUPER+? cheatsheet through prettyKeys — bind and
documentation stay one source. README row added.

Verified: V0; V1 — a scratch downstream with two entries renders both
binds (default command = lowercased class; custom mods/command/desc
honored), the script passes bash -n with a usage guard, and the
cheatsheet carries both rows. Focus behaviour needs a session -> V3
(HARDWARE-QUEUE).

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

agent/BACKLOG.md

@@ -214,11 +214,6 @@ the *same* outputs. **Plan (designed 2026-07-05, iteration #27):**
 - **Non-goals:** no kanshi (fights Hyprland's output management —
   decided in ROADMAP), nwg-displays stays a find-the-values helper.
 
-### 17. Launch-or-focus UX scripts
-ROADMAP § launch-or-focus. Hyprland dispatch scripts: a bind launches an
-app or focuses its existing window. Curate which apps get binds;
-cheatsheet entries via keybinds.nix.
-
 ### 18. "nomarchy" control center + first-boot welcome `[big]`
 ROADMAP § control center. A single front-end over the common toggles on
 the same `nomarchy-theme-sync` surface, + a first-boot guided