feat(config): add scratch terminal binding and window rule, remove pj function

dot_config/hypr/hyprland.lua

@@ -42,3 +42,8 @@ o.window([[^brave-youtube\.com__-Default$]], { workspace = "1" })
 o.window([[^brave-www\.tldraw\.com__-Default$]], { workspace = "3" })
 o.window([[^com\.fastmail\.Fastmail$]], { workspace = "4" })
 o.window([[^Beeper$]], { workspace = "4" })
+
+-- The SUPER + A scratch terminal (kitty --config ~/.config/kitty/herdr.conf).
+-- Pinning it here means it lands on the scratchpad no matter who starts it;
+-- "silent" leaves the reveal to omarchy-toggle-scratch.
+o.window([[^kitty-herdr$]], { workspace = "special:scratchpad silent" })