Add support for C# 12.0 features

[Jand42]

New language features: (See What’s new in C# 12)

• Generic math support - not planned, would not be efficient in JS, and provides nothing Macros/Inlines can't do
• Primary constructors for non-record classes
  • Tests added
• Collection expressions and .. operator
  • Tests added
• ref readonly parameters (added for API upgradeability purposes, no real new functionality, C# CodeReader needs to treat it the same as in)
  • Tests added
• Default lambda parameters - should be handled as other defaults
  • Tests added
• Inline arrays - not planned, .NET perf feature, not meant for end users
• Experimental attribute - C# compilation handles this to raise a warning, WS has nothing to do
• Interceptors - not planned, experimental feature