chore: import upstream snapshot with attribution

codec/protorpc/envelope.pb.micro.go

@@ -0,0 +1,21 @@
+// Code generated by protoc-gen-micro. DO NOT EDIT.
+// source: codec/protorpc/envelope.proto
+
+package protorpc
+
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package