Refuse a theme name that is shell syntax, and quote the one the unlock picker returns

A theme installed from a git repo is named after the repo URL, and that name
becomes its directory name under ~/.config/omarchy/themes. Style > Unlock built
a command line out of the name the picker returned and handed it to
omarchy-launch-floating-terminal-with-presentation, which runs its argument as a
shell string -- so a theme directory called `a';id;'b` ran `id`. Themes are
already held to contributing colour and nothing that executes, which is why
omarchy-theme-set stages no .lua, terminal config, or vscode.json from one.

Hold the derived name to the characters a theme name needs, which stops it from
being dangerous at every place it lands rather than at the one found, and quote
it with printf %q on the way into the action for the names already on disk.

omarchy-theme-remove keeps its existing path-climb guard: its name reaches only
a quoted rm, and the same charset would strand a theme installed before this.

Reported-by: Luis Alvarez (lalvarezt)

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011WFcUm5HWFyxaVYdwAeWPP

default/omarchy/omarchy-menu.jsonc

@@ -103,7 +103,7 @@
   // Style
   "style.theme": {"icon":"󰸌","label":"Theme","aliases":["theme","themes"],"action":"theme=$(omarchy-theme-switcher); [[ -n $theme ]] && omarchy-theme-set \"$theme\""},
   "style.background": {"icon":"","label":"Background","aliases":["background","wallpaper"],"action":"background=$(omarchy-theme-bg-switcher); [[ -n $background ]] && omarchy-theme-bg-set \"$background\""},
-  "style.unlock": {"icon":"󰟵","label":"Unlock","aliases":["unlock"],"action":"unlock=$(omarchy-plymouth-switcher); if [[ $unlock == default ]]; then omarchy-launch-floating-terminal-with-presentation omarchy-plymouth-reset; elif [[ -n $unlock ]]; then omarchy-launch-floating-terminal-with-presentation \"omarchy-plymouth-set-by-theme '$unlock'\"; fi"},
+  "style.unlock": {"icon":"󰟵","label":"Unlock","aliases":["unlock"],"action":"unlock=$(omarchy-plymouth-switcher); if [[ $unlock == default ]]; then omarchy-launch-floating-terminal-with-presentation omarchy-plymouth-reset; elif [[ -n $unlock ]]; then omarchy-launch-floating-terminal-with-presentation \"omarchy-plymouth-set-by-theme $(printf %q \"$unlock\")\"; fi"},
   "style.font": {"icon":"","label":"Font","provider":"fonts"},
   "style.bar": {"icon":"󰍜","label":"Menu Bar"},
   "style.bar.position": {"icon":"","label":"Position"},