Share verified reading context announcements with Remote

internal/app/speech_worker.go

@@ -108,6 +108,9 @@ type speechWorker struct {
 	speechContext  []atspi.Snapshot   // Same owner; replaced on each known navigation context.
 	indentationCue func(sound.Cue)
 
+	// Owned with speechContext by the serialized delivery goroutine.
+	speechContextObservation *tentacle.RemoteSpeechOutput
+
 	mutex              sync.Mutex
 	enabled            bool
 	mode               speechMode