v0.4.11: video frame ring buffer + decoder stats + 0.1s audio buffer

0.4.10 still played at ~2-5 fps even though the decoder buffer was
preallocated. Root cause: the single-slot staging buffer was paced by
SourceDataLine backpressure at the audio buffer's granularity (~0.5 s),
so the decoder burst-produced ~12 video frames into the slot while audio
drained, the consumer saw only the last frame of each burst, then the
decoder stalled until audio drained again. Net visible rate ~ source_fps
/ frames_per_burst.

Fix:
- Replace single staging slot with a 4-slot ring (preallocated, FIFO).
  Decoder writes to ringTail; if full, overwrites oldest and bumps
  droppedFrames so we can see overflow in the log. Render thread drains
  oldest under the same lock — no allocation, no race.
- Shrink audio driver buffer 0.5 s → 0.1 s so the decoder is paced more
  tightly. Burst size collapses from ~12 frames to 2-3, which fits
  inside the ring.
- Log decoder spec on start (WxH @ fps, audio Hz x ch, ring depth) and
  produced/consumed/dropped counters every ~10 s. Lets the user log
  confirm whether the decoder is keeping real-time pace and whether the
  ring is overflowing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

gradle.properties

@@ -5,7 +5,7 @@ org.gradle.configuration-cache=false
 
 # Mod
 mod_id=video_player
-mod_version=0.4.10
+mod_version=0.4.11
 maven_group=com.ejclaw.videoplayer
 archives_base_name=video_player