Rename ILSpy.Wpf.slnf -> ILSpy.Desktop.slnf with updated contents

The slnf name was a leftover from when ILSpy.csproj was WPF; its
contents are now the Avalonia desktop projects. Drop the dead
ILSpy.BamlDecompiler.csproj ref (the directory no longer holds a
project after the engine moved to ICSharpCode.BamlDecompiler) and the
out-of-scope items (TestPlugin, ILSpy.BamlDecompiler.Tests) -- they're
in neither ILSpy.sln nor any active build flow, so the slnf filter
surfacing them in IDE listings was just noise.

Assisted-by: Claude:claude-opus-4-7:Claude Code

ILSpy.Desktop.slnf

@@ -2,17 +2,15 @@
 	"solution": {
 		"path": "ILSpy.sln",
 		"projects": [
+			"ICSharpCode.BamlDecompiler\\ICSharpCode.BamlDecompiler.csproj",
 			"ICSharpCode.Decompiler.TestRunner\\ICSharpCode.Decompiler.TestRunner.csproj",
 			"ICSharpCode.Decompiler.Tests\\ICSharpCode.Decompiler.Tests.csproj",
 			"ICSharpCode.Decompiler\\ICSharpCode.Decompiler.csproj",
 			"ICSharpCode.ILSpyX\\ICSharpCode.ILSpyX.csproj",
-			"ILSpy.BamlDecompiler.Tests\\ILSpy.BamlDecompiler.Tests.csproj",
-			"ILSpy.BamlDecompiler\\ILSpy.BamlDecompiler.csproj",
-			"ICSharpCode.BamlDecompiler\\ICSharpCode.BamlDecompiler.csproj",
 			"ILSpy.ReadyToRun\\ILSpy.ReadyToRun.csproj",
+			"ILSpy.Tests.Windows\\ILSpy.Tests.Windows.csproj",
 			"ILSpy.Tests\\ILSpy.Tests.csproj",
-			"ILSpy\\ILSpy.csproj",
-			"TestPlugin\\TestPlugin.csproj"
+			"ILSpy\\ILSpy.csproj"
 		]
 	}
-}
+}