Make application transparency opt-in (#14253)

* Make application transparency opt-in

* Use the transparency helper for Kanagawa

* Address transparency review findings

* Toggle transparency for opaque windows too

migrations/1791123731.sh

@@ -0,0 +1,12 @@
+echo "Add an example for opting applications in to transparency"
+
+looknfeel="${XDG_CONFIG_HOME:-$HOME/.config}/hypr/looknfeel.lua"
+if [[ -f $looknfeel ]] && ! rg -Fq 'o.transparent_window("my-app")' "$looknfeel"; then
+  cat >>"$looknfeel" <<'LUA'
+
+-- Opt another application in to Omarchy's standard transparency.
+-- Find its class with: hyprctl clients
+-- o.transparent_window("my-app")
+-- o.transparent_window("my-app", "0.9 0.85") -- Custom active/inactive opacity.
+LUA
+fi