Feat: WIP terse code documentation

crates/ratatui/src/vu_meter.rs

@@ -1,3 +1,5 @@
+//! Stereo VU meter with dB-scaled level display.
+
 use crate::theme;
 use ratatui::buffer::Buffer;
 use ratatui::layout::Rect;
@@ -8,6 +10,7 @@ const DB_MIN: f32 = -48.0;
 const DB_MAX: f32 = 3.0;
 const DB_RANGE: f32 = DB_MAX - DB_MIN;
 
+/// Stereo VU meter displaying left/right levels in dB.
 pub struct VuMeter {
     left: f32,
     right: f32,