SooHwanCho

Results 3 issues of SooHwanCho

## Description This PR adds MapError Operator, which is transforms error upstream emits ## Checklist - [ ] this PR is based on the **main** branch and is up-to-date, if...

We encounterd our app crash on iOS 18.0 beta4. ```swift for str in ["1147e0286", "1147e02864"] { do { let decoder = JSONDecoder() print(str, try decoder.decode(Int.self, from: str.data(using: .utf8)!)) } catch...

As a result of PR #8 , It begin failing build under swift6. The reason for this is that `@retroactive` attribute is not supported for Swift6. I fixed it by...