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/services/Displays.qml

@@ -95,7 +95,6 @@ Singleton {
                 root.revertWithMessage("The display rejected that change and Panama restored the previous setting.");
                 return;
             }
-            verifyTimer.attempts = 0;
             verifyTimer.ticks = 0;
             verifyTimer.restart();
         }
@@ -107,7 +106,6 @@ Singleton {
             // Exit status is advisory only. Hyprland's Lua bridge can report
             // success without applying a value, so exact readback decides.
             root.revertVerificationActive = true;
-            revertVerifyTimer.attempts = 0;
             revertVerifyTimer.ticks = 0;
             revertVerifyTimer.restart();
         }
@@ -542,7 +540,6 @@ Singleton {
 
     Timer {
         id: verifyTimer
-        property int attempts: 0
         property int ticks: 0
         interval: 120
         repeat: true
@@ -552,14 +549,12 @@ Singleton {
                 root.verificationTimedOut();
                 return;
             }
-            if (root.refresh())
-                attempts++;
+            root.refresh();
         }
     }
 
     Timer {
         id: revertVerifyTimer
-        property int attempts: 0
         property int ticks: 0
         interval: 120
         repeat: true
@@ -569,8 +564,7 @@ Singleton {
                 root.revertVerificationTimedOut();
                 return;
             }
-            if (root.refresh())
-                attempts++;
+            root.refresh();
         }
     }