[CicadaPlayer] seek: Implementation of SeekInCache(int64_t pos)

Implementation of SuperMediaPlayer::SeekInCache(int64_t pos)

• The pos of seek is the pts value.
• The buffer is a list, so the inserted packets are inserted into the list in the order of arrival, that is, unsorted.
• The pts of the package should normally be monotonic and continuous.
• Even if it's not monotonically continuous, the cache doesn't care.
• The seek operation mainly compares pos and mCurrentPos first.
• pos is smaller than mCurrentPos, then backward, backward is to search pts from the cache
• Looking forward is also in the cache.

The media packet queue is a list: linked list

        std::list<mediaPacket> mQueue;

mPlayedAudioPts is initialized to INT64_MIN

        int64_t mPlayedAudioPts{
   
    
    INT64_MIN