Add repeatable argument to the directive

…  schema representation.

CHANGELOG.md

@@ -7,9 +7,16 @@ and this project adheres to
 [Haskell Package Versioning Policy](https://pvp.haskell.org/).
 
 ## [Unreleased]
+### Changed
+- `Schema.Directive` is extended to contain a boolean argument, representing
+  repeatable directives.
+
 ### Fixed
 - `gql` quasi quoter recognizeds all GraphQL line endings (CR, LF and CRLF).
 
+### Added
+- @specifiedBy directive.
+
 ## [1.3.0.0] - 2024-05-01
 ### Changed
 - Remove deprecated `runCollectErrs`, `Resolution`, `CollectErrsT` from the