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>

modules/home/rofi.nix

@@ -125,6 +125,12 @@ let
     map (b: padRight 22 (prettyKeys b) + b.desc) (keybinds.binds
       ++ lib.optionals (lib.hasInfix "," cfg.keyboard.layout)
          keybinds.multiLayoutBinds)
+    # Launch-or-focus binds (nomarchy.launchOrFocus, generated in
+    # hyprland.nix) — same renderer, so they land in the cheatsheet too.
+    ++ map (e: padRight 22 (prettyKeys e)
+               + (if e.desc != "" then e.desc
+                  else "Focus or launch ${if e.command == "" then lib.toLower e.class else e.command}"))
+         cfg.launchOrFocus
     ++ map (e: padRight 22 e.keys + e.desc) keybinds.extra;
   cheatsheetFile = pkgs.writeText "nomarchy-keybinds.txt"
     (lib.concatStringsSep "\n" cheatRows + "\n");