Make every settings page reachable from the launcher

Settings had a search index and the launcher had script commands, and
neither knew about the other: finding a setting meant opening Settings
first and searching there. One command per page is now generated from
the same sources the in-app search reads -- the sidebar page list, the
group routing, and the schema labels -- so a setting searchable inside
Settings is searchable from the launcher without a second list to
maintain.

Generating it surfaced a gap in the in-app search as well. Six pages had
no vocabulary at all, because their contents come from the system rather
than our schema, so searching "volume" found nothing in Settings either.
They now carry entries, which improves both surfaces.

The product prefix is dropped from every hand-written command title. The
generated ones are qualified "Settings: <page>" instead: a bare page
label collides with the feature of the same name, and two commands
sharing a title are indistinguishable in a launcher.

Claude-Session: https://claude.ai/code/session_01BRvzt4H8XXLPVH5MyYdk9L

config/dot/quickshell/services/SettingsSearch.qml

@@ -64,6 +64,22 @@ Singleton {
         { label: "Bluetooth", detail: "Managed by GNOME Settings", page: "connectivity" },
         { label: "Printers", detail: "Managed by GNOME Settings", page: "connectivity" },
         { label: "Default applications", detail: "Browser, mail, files", page: "applications" },
+        { label: "Output volume", detail: "Choose the output device and its level", page: "sound" },
+        { label: "Input volume", detail: "Choose the microphone and its level", page: "sound" },
+        { label: "Per-application volume", detail: "Set the level of each application separately", page: "sound" },
+        { label: "Event sounds", detail: "Play alerts and interface event sounds", page: "sound" },
+        { label: "Saved passwords", detail: "The login keyring and what is stored in it", page: "privacy" },
+        { label: "Camera and microphone", detail: "Which applications may use them", page: "privacy" },
+        { label: "Screen sharing", detail: "Which applications may capture the screen", page: "privacy" },
+        { label: "File history and trash", detail: "What is remembered and when it is cleared", page: "privacy" },
+        { label: "Device security", detail: "Secure boot and firmware protections", page: "privacy" },
+        { label: "Language", detail: "The system language, applied to programs started afterwards", page: "region" },
+        { label: "Regional formats", detail: "How dates, times, and numbers are written", page: "region" },
+        { label: "Online accounts", detail: "Sign in to mail, calendar, and contacts", page: "accounts" },
+        { label: "Home Assistant", detail: "Connect the desktop to a Home Assistant server", page: "home-phone" },
+        { label: "Phone", detail: "Pair a phone for messages and notifications", page: "home-phone" },
+        { label: "System information", detail: "Kernel, distribution, and hardware", page: "about" },
+        { label: "Desktop version", detail: "Which Hyprland and Quickshell this session runs", page: "about" },
         { label: "Restore defaults", detail: "Return every Panama setting to its shipped value", page: "desktop" },
         { label: "Keyboard shortcuts", detail: "Every shortcut the compositor has bound", page: "shortcuts" },
         { label: "System Health", detail: "Check Panama services, integrations, tools, and recovery actions", page: "services" },