[HLSL] Frontend handling of "typed" resource types and buffer operations

[damyanp]

• [HLSL] Implement intangible AST type #97362
• [HLSL] Move resource attributes to resource's handles instead of the class itself #98556
• [HLSL] Split [[hlsl::resource_class]] out of the HLSLResource attribute #98193
• [HLSL] Move resource attributes to resource's handles instead of the class itself #98556
• Split [[clang::hlsl_is_rov]] out of the HLSLResource attribute #102392
• [HLSL] Add __is_intangible type trait #102954
• [HLSL] Define the hlsl::contained_type attribute #104855
• [HLSL] Add an attribute to differentiate resource attributes for Buffer vs StructuredBuffer and RawBuffer #107907
• [HLSL] Apply hlsl resource attributes to the resource type rather than the handle member #104861
• Proposal for how resource attributes will map to DXIL and SPIR-V wg-hlsl#68
• [HLSL] Add DirectXTargetCodeGenInfo and the code paths to convert HLSL types to DirectX target types #95952
• [HLSL] Introduce builtins to index into HLSLResource types #95956
• [HLSL] Replace void * handles in HLSLExternalSemaSource with HLSLResource builtin types #84824
• [HLSL] Emit dx.handle.fromBinding instead of dx.create_handle when resource is created  #105076
• [HLSL] Document HLSL buffer types in the language spec wg-hlsl#56