升级 Microsoft.CodeAnalysis.CSharp 和添加文件范围命名空间支持

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1. 原来的 Microsoft.CodeAnalysis.CSharp 是 4.2.0 版本的，包含 C# 版本为 C# 10。升级到 4.8.0 以支持 C# 11 和 C# 12 的语法，例如列表模式匹配。如果不升级，在使用列表模式匹配+属性模式匹配时会解析类的范围。
2. 块范围的命名空间与文件范围的命名空间（C# 10 已支持）在语法解析中是不同的语法节点，需要额外添加对文件范围命名空间的处理。

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@SeWZC 构建失败：

        "D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj" (default target) (7:6) ->
       (CoreCompile target) -> 
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(23,87): error CS8795: Partial method 'Program.ExportFooEnumerable()' must have an implementation part because it has accessibility modifiers. [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(26,64): error CS8795: Partial method 'Program.ExportF1Enumerable()' must have an implementation part because it has accessibility modifiers. [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(22,29): error CS0234: The type or namespace name 'TelescopeExportAttributeAttribute' does not exist in the namespace 'dotnetCampus.Telescope' (are you missing an assembly reference?) [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(22,29): error CS0234: The type or namespace name 'TelescopeExportAttribute' does not exist in the namespace 'dotnetCampus.Telescope' (are you missing an assembly reference?) [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(22,54): error CS0246: The type or namespace name 'IncludeReferences' could not be found (are you missing a using directive or an assembly reference?) [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(25,29): error CS0234: The type or namespace name 'TelescopeExportAttributeAttribute' does not exist in the namespace 'dotnetCampus.Telescope' (are you missing an assembly reference?) [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(25,29): error CS0234: The type or namespace name 'TelescopeExportAttribute' does not exist in the namespace 'dotnetCampus.Telescope' (are you missing an assembly reference?) [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]
         D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\Program.cs(25,54): error CS0246: The type or namespace name 'IncludeReferences' could not be found (are you missing a using directive or an assembly reference?) [D:\a\SourceFusion\SourceFusion\src\TelescopeSourceGenerator\Demo\TelescopeSourceGeneratorDemo\dotnetCampus.Telescope.SourceGeneratorAnalyzers.Demo.csproj]

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构建没通过