Fix .gitignore alphabetical ordering

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Co-Authored-By: Claude <[email protected]>

Author: si618

.gitignore

@@ -1,7 +1,7 @@
+.plan
 .vs
+*.DotSettings.user
 bin
 obj
-*.DotSettings.user
 BenchmarkDotNet.Artifacts
 /.idea/.idea.LeetCode/.idea/material_theme_project_new.xml
-.plan