feat(quickshell): replace fuzzel with an in-process launcher

fuzzel could only answer "which app", so launching Brave at a URL meant
picking the app, waiting for it, then typing the address somewhere else.
The launcher now takes a verb and an object in one line: type
`gitlab.enqs.de` and every app that can open it sorts to the top, default
browser first, ready for Enter — or arrow/hjkl down to Brave's New
Incognito Window, which is offered as a peer of Brave itself rather than
hidden behind a submenu.

services/Apps.qml is the brain and holds no UI: it flattens desktop
entries and their actions into one index, classifies the typed argument
(url / mail / path), ranks by fuzzy match plus handler affinity plus
frecency, and launches. Launching through `uwsm app` keeps each app in its
own scope; entries whose Exec declares no field code (Brave's
`--incognito` action, among others) are launched by tokenising Exec per
the Desktop Entry spec and appending the argument, never via `sh -c`.

Four prefixes reuse the same window, so there is one picker and one set of
keys: `>` runs a command, `=` evaluates arithmetic, `:` is clipboard
history (cliphist, which had been a second fuzzel invocation), and a
dmenu mode is driven over IPC.

quickshell/scripts/takemi-dmenu is the bridge for that last one — a
`fuzzel --dmenu` drop-in for scripts that want a picker, symlinked into
~/.local/bin. fluxo's bt menu now goes through it.

Living in the Quickshell process means the window is on screen on the
frame the bind fires, with no process to spawn.

Removes fuzzel entirely: its config, its theme submodule, the package,
and the last consumers (the bar sigil, fluxo's menu_command). Also drops
hypr/scripts/powermenu.sh, which was fuzzel-based and bound to nothing.

quickshell/bar/Sigil.qml

@@ -17,7 +17,7 @@ BarPill {
     lean: Theme.skew
     implicitWidth: Theme.barHeight + contentPad
 
-    onClicked: Actions.launch("fuzzel")
+    onClicked: Actions.toggleLauncher()
     onRightClicked: Actions.reloadShell()
 
     // The wordmark. Was the Death arcana skull (nf-md-skull, U+F068C) — a