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/hypr/DESKTOP-PARITY.md

@@ -77,7 +77,7 @@ than presenting inert Hyprland controls.
 | Caffeine | Replaced by a real logind inhibitor in quick settings |
 | Blur My Shell / Openbar / User Theme | Replaced by the Prism shell and compositor blur |
 | Bluetooth Quick Connect | Replaced by the full Bluetooth picker |
-| Wi-Fi QR | Deliberately omitted; it is not useful enough to justify another credential-reading surface |
+| Wi-Fi QR | Replaced by an on-demand QR-code sharing flow in Control Center's Wi-Fi panel; the code is generated only while shown and written to tmpfs, never persisted |
 | GSConnect | Replaced by capability-aware KDE Connect phone continuity in Control Center; the paired iPhone exposes file, clipboard, and Ring actions when reachable |
 | Home Assistant | Replaced by secure favourites in Control Center; explicit private environment values take precedence over the existing GNOME extension and Secret Service setup |
 | Custom Hot Corners Extended | No action was configured, so there is no behavior to port |