Simplify service lookups with optional chaining

The bar-null-shell-null-typeof-function ternary guarded against our own
shell missing a method it always defines. bar?.shell?.firstPartyServiceFor()
handles the only real case, delayed bar injection, in one line. The
typeof checks that probe genuinely third-party plugin objects stay.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

shell/plugins/notifications/BarWidget.qml

@@ -25,9 +25,7 @@ BarWidget {
 
   // Look up the long-running notifications service through the shell host.
   readonly property var hostShell: bar && bar.shell ? bar.shell : null
-  readonly property var notificationService: hostShell && typeof hostShell.firstPartyServiceFor === "function"
-    ? hostShell.firstPartyServiceFor("omarchy.notifications")
-    : null
+  readonly property var notificationService: hostShell?.firstPartyServiceFor("omarchy.notifications")
 
   function isChromiumDerived(app, appIcon) {
     return NotificationLogic.isChromiumDerived(app, appIcon)