[mirotalksfu] - improve RTMP Streamer UI

public/views/Room.html

@@ -1017,6 +1017,9 @@ access to use this app.
                                 <hr />
                             </div>
                             <div id="rtmpFromStream">
+                                <p>
+                                    Select your desired video and audio sources from settings, then begin RTMP streaming
+                                </p>
                                 <button id="streamerRtmpButton" class="hidden btn-custom">
                                     <i class="fa-solid fa-satellite-dish"></i>&nbsp;RTMP Streamer
                                 </button>