fix: UTF-16BE skill files keep their byte order during setup

Assets/Tests/Editor/SkillFileContentNormalizerTests.cs

@@ -57,6 +57,46 @@ public void NormalizeSkillFileContent_WhenUtf16BigEndianTextUsesCrlf_PreservesEn
             Assert.That(actualBytes, Is.EqualTo(expectedBytes));
         }
 
+        // Tests that an explicit big-endian BOM wins over byte patterns that resemble little-endian CR.
+        [Test]
+        public void NormalizeSkillFileContent_WhenUtf16BigEndianBomContainsAmbiguousCodeUnit_PreservesEncoding()
+        {
+            byte[] sourceBytes = Encoding.BigEndianUnicode.GetPreamble()
+                .Concat(Encoding.BigEndianUnicode.GetBytes("\u0D00\r\nline"))
+                .ToArray();
+            byte[] expectedBytes = Encoding.BigEndianUnicode.GetPreamble()
+                .Concat(Encoding.BigEndianUnicode.GetBytes("\u0D00\nline"))
+                .ToArray();
+
+            byte[] actualBytes = SkillFileContentNormalizer.NormalizeSkillFileContent("reference.md", sourceBytes);
+
+            Assert.That(actualBytes, Is.EqualTo(expectedBytes));
+        }
+
+        // Tests that BOM-less UTF-16 little-endian text still uses line-ending heuristics.
+        [Test]
+        public void NormalizeSkillFileContent_WhenUtf16LittleEndianHasNoBom_NormalizesCrlf()
+        {
+            byte[] sourceBytes = Encoding.Unicode.GetBytes("line1\r\nline2\r\n");
+            byte[] expectedBytes = Encoding.Unicode.GetBytes("line1\nline2\n");
+
+            byte[] actualBytes = SkillFileContentNormalizer.NormalizeSkillFileContent("reference.md", sourceBytes);
+
+            Assert.That(actualBytes, Is.EqualTo(expectedBytes));
+        }
+
+        // Tests that BOM-less UTF-16 big-endian text still uses line-ending heuristics.
+        [Test]
+        public void NormalizeSkillFileContent_WhenUtf16BigEndianHasNoBom_NormalizesCrlf()
+        {
+            byte[] sourceBytes = Encoding.BigEndianUnicode.GetBytes("line1\r\nline2\r\n");
+            byte[] expectedBytes = Encoding.BigEndianUnicode.GetBytes("line1\nline2\n");
+
+            byte[] actualBytes = SkillFileContentNormalizer.NormalizeSkillFileContent("reference.md", sourceBytes);
+
+            Assert.That(actualBytes, Is.EqualTo(expectedBytes));
+        }
+
         // Tests that files outside the text extension allowlist keep their original bytes.
         [Test]
         public void NormalizeSkillFileContent_WhenExtensionIsNotText_ReturnsOriginalContent()

Packages/src/Editor/Infrastructure/SkillSetup/SkillFileContentNormalizer.cs

@@ -39,12 +39,22 @@ internal static byte[] NormalizeSkillFileContent(string relativePath, byte[] con
                 return content;
             }
 
-            if (HasUtf16LittleEndianBom(content) || HasUtf16LittleEndianLineEnding(content))
+            if (HasUtf16LittleEndianBom(content))
             {
                 return NormalizeUtf16LineEndings(content, isLittleEndian: true);
             }
 
-            if (HasUtf16BigEndianBom(content) || HasUtf16BigEndianLineEnding(content))
+            if (HasUtf16BigEndianBom(content))
+            {
+                return NormalizeUtf16LineEndings(content, isLittleEndian: false);
+            }
+
+            if (HasUtf16LittleEndianLineEnding(content))
+            {
+                return NormalizeUtf16LineEndings(content, isLittleEndian: true);
+            }
+
+            if (HasUtf16BigEndianLineEnding(content))
             {
                 return NormalizeUtf16LineEndings(content, isLittleEndian: false);
             }