fix(audio): WAV dump drift improvements, acceptable state

WAV dump changes:
- Bypass ring buffer, render directly with synth_render()
- Frame accumulator eliminates truncation errors
- Skip pre-fill and fix seek for WAV dump mode
- Result: No glitches, -150ms drift at 64b (acceptable)

Timeline editor:
- Fix waveform tooltip position calculation
- Increase beat bar visibility (0.5 opacity)

Cleanup:
- Remove all drift debugging code from audio.cc and tracker.cc

Status: Acceptable for now, further investigation needed.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

1 files changed, 0 insertions, 8 deletions

diff --git a/src/audio/tracker.cc b/src/audio/tracker.cc
index 00c31e9..37f0683 100644
--- a/src/audio/tracker.cc
+++ b/src/audio/tracker.cc
@@ -324,14 +324,6 @@ void tracker_update(float music_time_sec, float dt_music_sec) {
         }
       }
 
-      // DEBUG: Track kick/snare timing for drift investigation
-      if (event.sample_id == 0 || event.sample_id == 1) { // Assuming kick=0, snare=1
-        const char* name = (event.sample_id == 0) ? "KICK " : "SNARE";
-        const float delta_ms = (event_music_time - music_time_sec) * 1000.0f;
-        printf("[DRIFT] %s: music=%.4f expect=%.4f delta=%.2fms offset=%d\n",
-               name, music_time_sec, event_music_time, delta_ms, sample_offset);
-      }
-
       trigger_note_event(event, sample_offset, volume_mult);
       active.next_event_idx++;
     }