Remove dead shell components and fix stale docs

NotificationCenter.qml, CalendarPopup.qml, and RecordingIndicator.qml
were never instantiated anywhere -- shell.qml builds NotificationList,
DateMenu, and CaptureOverlay in their place. Verified with a repo-wide
grep before deleting; updated the two stale comments in Notifs.qml
that still pointed at NotificationCenter.

DESKTOP-PARITY.md still described Wi-Fi QR sharing as deliberately
omitted, though it was since built. The System Health colour-profile
handoff pointed at GNOME's colour panel as if it worked, but the
daemon that actually loads an ICC profile doesn't run in this session,
so it silently does nothing -- reworded the card to say so. Displays
carried two verify-timer attempt counters that were incremented but
never read anywhere.

Claude-Session: https://claude.ai/code/session_01E6TJUAh41HaP25MVHWkhRZ

config/dot/quickshell/modules/settings/HealthPage.qml

@@ -441,7 +441,7 @@ SettingsPage {
         ActionRow {
             objectName: "health-fedora-handoff:color"
             label: "Colour profiles"
-            detail: "ICC profiles for displays, printers, and scanners"
+            detail: "Assigning an ICC profile here has no visible effect in this session: the colord daemon that loads it onto a display isn't running under Hyprland"
             action: "Open colour"
             onTriggered: SystemSettings.openGnomePanel("color")
         }