docs: v1.9.0 comment-pass (Z-3) — fix false TEST-MIRROR paths, comment accuracy + density

HellionChat/Ui/StyleEngine/DrawListExtensions.cs

@@ -12,7 +12,6 @@ namespace HellionChat.Ui.StyleEngine;
 // ABGR before delegating to ImDrawList. Hover-sheen state lives in a small
 // static dictionary keyed by constant strings — keep keys constant and
 // scope to static UI elements so the per-key footprint stays bounded.
-// TEST-MIRROR: Util/ColourUtilTintTests.cs
 internal static class DrawListExtensions
 {
     private const float SheenDurationSeconds = 0.65f;
@@ -22,7 +21,7 @@ internal static class DrawListExtensions
     // highlight, not a saturated accent flash (effect level "subtle").
     private const float SheenTintStrength = 0.35f;
 
-    // A2 tuning knob: peak alpha at t=0, fading linearly to 0 over the sweep.
+    // Peak sheen alpha (low so the highlight stays subtle); DrawHoverSheen applies the falloff.
     private const byte SheenPeakAlpha = 0x40;
 
     private static readonly Dictionary<string, DateTime> SheenStarts = new();