Document PAK v2 resource closeout

src/AcDream.Content/Pak/PakFormat.cs

@@ -30,7 +30,8 @@ public static class PakFormat {
     /// 8 polygons all NoPos + Base1Solid, extracted to a 0-vertex mesh). The
     /// binary format remains version 1. Version 6 introduces pak format 2:
     /// globally shared texture payloads plus independently Brotli-compressed
-    /// blobs with raw fallback. Mesh geometry and decoded pixels remain exact.
+    /// blobs with raw fallback. Mesh geometry and source texture bytes remain
+    /// exact; unedited DXT surfaces now retain their native BC blocks.
     /// </summary>
     public const uint CurrentBakeToolVersion = 6;
 }