fix(iv): gate jwt-invalidated listener add/remove on init

Match the init-readiness pattern used by updateUserJwt: when background
threading is enabled, waitForInit; otherwise throw if not initialized.
Without this, listeners added before initWithContext silently bind to a
not-yet-wired UserManager.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: nan-li

OneSignalSDK/onesignal/core/src/main/java/com/onesignal/internal/OneSignalImp.kt

@@ -453,10 +453,24 @@ internal class OneSignalImp(
     }
 
     override fun addUserJwtInvalidatedListener(listener: IUserJwtInvalidatedListener) {
+        if (isBackgroundThreadingEnabled) {
+            waitForInit(operationName = "addUserJwtInvalidatedListener")
+        } else {
+            if (!isInitialized) {
+                throw IllegalStateException("Must call 'initWithContext' before 'addUserJwtInvalidatedListener'")
+            }
+        }
         services.getService<UserManager>().addJwtInvalidatedListener(listener)
     }
 
     override fun removeUserJwtInvalidatedListener(listener: IUserJwtInvalidatedListener) {
+        if (isBackgroundThreadingEnabled) {
+            waitForInit(operationName = "removeUserJwtInvalidatedListener")
+        } else {
+            if (!isInitialized) {
+                throw IllegalStateException("Must call 'initWithContext' before 'removeUserJwtInvalidatedListener'")
+            }
+        }
         services.getService<UserManager>().removeJwtInvalidatedListener(listener)
     }