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/README.md

@@ -199,8 +199,9 @@ Persona 3's blue and nothing else needs touching.
   `fish_frozen_theme.fish` that fish 4.3 generated on upgrade. The prompt arrow
   is white and turns crimson on a non-zero exit — the shell's one "wrong"
   signal, and so the one place that earns the accent.
-- **Fuzzel** — `fuzzel/takemi.ini`, selected by the `include` in `fuzzel.ini`.
-  Square corners rather than the stock radius, and a fully opaque ground.
+- **The launcher** — no external theming to keep in step, because it is part of
+  this shell (`launcher/`). Fuzzel is gone; `takemi-dmenu` stands in for
+  `fuzzel --dmenu` where a script needs a picker.
 - **No glass anywhere.** Alacritty is `opacity = 1.0, blur = false`, and
   Hyprland's `decoration:blur` is disabled with both opacities at `1.0`. Blur is
   the signature of the frosted-glass look, which is the opposite of flat ink on