Update .editorconfig for C# coding style preferences

Enhanced C# coding standards in the .editorconfig file.
Key changes include preference for top-level statements,
encouragement of primary constructors, and mandatory braces
for control statements. Additionally, simple using statements
are suggested, namespace declarations are set to file-scoped,
and method group conversion is silenced. Expression-level
preferences have been refined, favoring simple default
expressions and inlined variable declarations, while
disallowing deconstructed variable declarations.

Author: AngeloDotNet

.editorconfig

@@ -131,7 +131,6 @@ csharp_prefer_braces = true:silent
 csharp_prefer_simple_using_statement = true:suggestion
 csharp_style_namespace_declarations = file_scoped:suggestion
 csharp_style_prefer_method_group_conversion = true:silent
-csharp_prefer_system_threading_lock = true:suggestion
 
 # Expression-level preferences
 csharp_prefer_simple_default_expression = true:suggestion