Recover streams after five seconds and start from complete keys

Preserve queued media under backpressure, advertise retained keyframe ranges in stream wire v6, and reopen stalled subflows without resetting playback.

Cover large fragmented keys, sustained slow delivery, missing subflows, buffer eviction and stale bootstrap snapshots in integration regressions.

tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamPlayerEngine.kt

@@ -90,7 +90,6 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
         var video: StreamVideoPlayback? = null
         var waitingKey = true
         var audioEnabled = false
-        var opened = false
         var ended = false
         var videoInputEnded = false
         var audioInputEnded = false
@@ -113,7 +112,6 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
         var underrunBase = 0L
         var silenceBase = 0L
         var workMaxUs = 0L
-        var deadline = System.nanoTime() + 10_000_000_000
         var clockState: LongArray? = null
 
         fun observeStatus(meta: LongArray?) {
@@ -139,7 +137,7 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
             playback = null; position = -1; generation = 0; needsAudio = true; clockState = null; playbackStarted = false
             underrunBase = 0; silenceBase = 0
             records.clear(); ended = false; videoInputEnded = false; audioInputEnded = false; endUntil = 0
-            resetVideo(); deadline = System.nanoTime() + 10_000_000_000
+            resetVideo()
             if (request) check(NativeLib.streamResync(id)) { "Media resync refused" }
         }
         try {
@@ -180,7 +178,6 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
                         1 -> {
                             if (revision != videoRevision) {
                                 check(revision > videoRevision); resetVideo(); videoRevision = revision
-                                deadline = System.nanoTime() + 10_000_000_000
                             }
                             val key = flags and 1 != 0
                             if (!waitingKey || key) {
@@ -203,7 +200,7 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
                             if (result == -2) resetTimeline(true) else check(result >= 0) { "Opus feed failed=$result" }
                         }
                         3 -> { LogManager.addLog("INFO", "stream", "playback GAP id=$id"); resetTimeline(false) }
-                        4 -> opened = true
+                        4 -> Unit
                         5, 7, 8 -> {
                             if (kind != 8 && !videoInputEnded) { videoInputEnded = true; video.finish() }
                             if (kind != 7 && !audioInputEnded) { audioInputEnded = true; playback?.finish() }
@@ -224,7 +221,7 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
                     }
                 }
                 if (!running) break
-                if (!ended && (!opened || waitingKey) && System.nanoTime() > deadline) error("Viewer open timeout")
+                // Ядро перезапрашивает DATA после 5с без прогресса; большой KEY может собираться дольше.
                 val decoded = video.state
                 if (!playbackStarted && decoded.firstOutputPts != null) playbackStarted = true
                 if (playbackStarted && playback != null && ready >= 0) {