rpc: Rename SingletonId to SingleIdResponse
Calling it "singleton" might have suggested that it was using the singleton pattern, which it isn't.
(Renaming done with rust-analyzer and double-checked with git grep.)
Closes #1585 (closed).
Calling it "singleton" might have suggested that it was using the singleton pattern, which it isn't.
(Renaming done with rust-analyzer and double-checked with git grep.)
Closes #1585 (closed).