✨ Update usage grpc call

pkg/proto/attachment.proto

@@ -8,6 +8,7 @@ service AttachmentService {
   rpc GetAttachment(GetAttachmentRequest) returns (GetAttachmentResponse) {}
   rpc ListAttachment(ListAttachmentRequest) returns (ListAttachmentResponse) {}
   rpc UpdateVisibility(UpdateVisibilityRequest) returns (UpdateVisibilityResponse) {}
+  rpc UpdateUsage(UpdateUsageRequest) returns (UpdateUsageResponse) {}
   rpc DeleteAttachment(DeleteAttachmentRequest) returns (DeleteAttachmentResponse) {}
 }
 
@@ -53,6 +54,15 @@ message UpdateVisibilityResponse {
   int32 count = 1;
 }
 
+message UpdateUsageRequest {
+  repeated uint64 id = 1;
+  int64 delta = 2;
+}
+
+message UpdateUsageResponse {
+  int32 count = 1;
+}
+
 message DeleteAttachmentRequest {
   repeated uint64 id = 1;
   repeated string rid = 2;