Fix IOSLiveActivitiesUpdated not firing after start() on iOS 17.2+ (#132)

On iOS 17.2+, start() skipped checkForActivities() assuming pushToStartTokenUpdates
would trigger watcher setup. That stream fires at launch/token refresh but not on
direct app-initiated starts, so no state changes were ever observed for the new activity.

Fix: set up the watcher and emit the initial event inline after start() on iOS 17.2+,
mirroring what checkForActivities() would have done. Guarded by activityState nil check
so it's a no-op if a concurrent pushToStartTokenUpdates already handled it.

Author: crow

ios/AirshipFrameworkProxy/LiveActivity/LiveActivityManager.swift

@@ -154,6 +154,12 @@ public actor LiveActivityManager: Sendable {
         let result = try await findEntry(attributesType: request.attributesType).start(request)
         if #unavailable(iOS 17.2) {
             await self.checkForActivities()
+        } else if activityState[result.id] == nil {
+            // On iOS 17.2+, checkForActivities() is not called on start (pushToStartTokenUpdates
+            // handles discovery at launch), so set up watching for the new activity directly.
+            await startWatchingActivityUpdates(result.id, attributesType: request.attributesType)
+            await updated(activityID: result.id, info: result, notifyOnChange: false)
+            await notify()
         }
         return result
     }