Add FieldLiteral proto message

private/pkg/protosource/option_extension_descriptor.go

@@ -127,7 +127,7 @@ func isDescendantPath(descendant, ancestor []int32) bool {
 	return true
 }
 
-func (o *optionExtensionDescriptor) Range(fn func(protoreflect.FieldDescriptor, protoreflect.Value) bool) {
+func (o *optionExtensionDescriptor) ForEachFieldDescriptor(fn func(protoreflect.FieldDescriptor, protoreflect.Value) bool) {
 	// Note: This does not bother to handle unrecognized fields.
 	// Should not be a problem since descriptors models in the buf CLI codebase should have them
 	// all correctly parsed and known.

private/pkg/protosource/protosource.go

@@ -152,9 +152,10 @@ type OptionExtensionDescriptor interface {
 	// have a set value on this descriptor.
 	PresentExtensionNumbers() []int32
 
-	// Range implements the same interface as protoreflect.Message. This takes
-	// in a callback that iterates over a protoreflect message field descriptors and values.
-	Range(fn func(protoreflect.FieldDescriptor, protoreflect.Value) bool)
+	// ForEachFieldDescriptor iterates through all fields present in the options message invoking
+	// the callback for each one. If the callback returns false, it terminates the
+	// iteration and returns immediately.
+	ForEachFieldDescriptor(fn func(protoreflect.FieldDescriptor, protoreflect.Value) bool)
 }
 
 // Location defines source code info location information.