SDK / exoplayer

This simplifies the addition of new fields in the future.

Also do some misc clean up for the volume limit values:
 - Add some documentation to mention assumed defaults
 - Add the IntRange annotations to match the ones we have in Player
   already
 - Mention the limits in the relevant Player methods
 - Avoid bundling default values
 - Improve range checks for masking in MediaController

PiperOrigin-RevId: 526029619