[inputstream.adaptive] Fix audio deadlock on quality STREAMCHANGE

When a bandwidth fluctuation triggered a representation change, Kodi
Core handled the `DEMUX_SPECIALID_STREAMCHANGE` packet by sequentially
reopening all active streams (e.g., Video 1001, then Audio 1014).

If the first stream (Video) evaluated to no quality change,
`CInputStreamAdaptive::OpenStream` set the `m_checkCoreReopen = true`
optimization flag to short-circuit further sequence callbacks.
However, because this block always returned `true`, if the
subsequent stream (Audio) *did* change quality, its formal
[Reset()](AdaptiveStream.h) and reconstruction was skipped entirely.

The bypassed stream's state remained stuck at
`EVENT_TYPE::REP_CHANGE`, causing the fragmented sample
reader to permanently block new segment downloads, yielding
a continuous `AP4_ERROR_EOS` loop and stalling playback.

This commit hoists the `!streamChanged` conditional to guard
the entire `m_checkCoreReopen` block, guaranteeing that a formally
changed stream will bypass the fast-path optimization and execute
its native `Reset()` cycle preventing the permanent `EOS` stall.

Author: linzack

src/main.cpp

@@ -221,20 +221,19 @@ bool CInputStreamAdaptive::OpenStream(int streamid)
     }
   }
 
-  if (m_checkCoreReopen)
+  bool streamChanged{stream->m_adStream.StreamChanged()};
+  
+  if (m_checkCoreReopen && !streamChanged)
   {
-    LOG::Log(LOGDEBUG, "OpenStream(%d): The stream has already been opened", streamid);
-
     // If the reader is in EOS from a transient failure during STREAMCHANGE,
     // reset it so audio can resume
     auto reader = stream->GetReader();
-    bool isEos = reader && reader->EOS();
-    bool streamChanged = stream->m_adStream.StreamChanged();
+    bool isEos{reader && reader->EOS()};
 
-    LOG::Log(LOGDEBUG, "OpenStream(%d): Checking recovery. isEos=%d streamChanged=%d", 
+    LOG::Log(LOGDEBUG, "OpenStream(%d): The stream has already been opened. Checking recovery. isEos=%d streamChanged=%d", 
              streamid, isEos, streamChanged);
 
-    if (isEos && !streamChanged)
+    if (isEos)
     {
       LOG::Log(LOGINFO, "OpenStream(%d): Recovering stream from transient EOS", streamid);
       reader->Reset(false); // Clear EOS