Fix function array argument calling convention

[davispuh]

C language allows function definitions to be like:

GLAPI void GLAPIENTRY glLoadTransposeMatrixd( const GLdouble m[16] )

But currently such definitions create invalid FFI type:

TypeError: unable to resolve type '[:double, 16]' (TypeError)

        raise TypeError, "unable to resolve type '#{name}'"
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This PR fixes this by correctly defining it as pointer type.
So now with this PR and with #9 rake test completes successfully.

[Copilot]

Pull request overview

Adjusts generated Ruby FFI signatures so C array parameters (e.g., const double m[16]) are emitted as pointer types in function/callback signatures, avoiding invalid FFI array type resolution errors.

Changes:

• Add an optional usecase parameter to ruby_ffi_type across type classes to allow context-sensitive type emission.
• Emit :pointer for ArrayType when used as a function argument, while retaining array literals for struct/union layouts.
• Update function/callback signature generation to call ruby_ffi_type(:function_argument) for parameters.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
lib/ffi_generator/generators/from_c_generator/unknown_type.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/struct_or_union.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/string_type.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/primitive_type.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/pointer_type.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/function_or_callback.rb	Passes :function_argument context when generating parameter FFI signatures.
lib/ffi_generator/generators/from_c_generator/enum.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/by_value_type.rb	Updates ruby_ffi_type signature to accept a context parameter.
lib/ffi_generator/generators/from_c_generator/array_type.rb	Emits :pointer for function-argument arrays; keeps array literals elsewhere.

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[Copilot]

ByValueType accepts the new usecase argument but doesn’t forward it to @inner_type.ruby_ffi_type. To keep behavior consistent (and avoid future context-specific type mismatches), pass usecase through when calling the inner type.

Suggested change

	"#{@inner_type.ruby_ffi_type}.by_value"
	"#{@inner_type.ruby_ffi_type(usecase)}.by_value"