[scala-sttp4-jsoniter] add generic Option and Seq codecs for jsoniter-scala

[reynaldjoabet]

Add generic JsonValueCodec instances for Option[A] and Seq[A] directly
in JsonSupport, derived via deriveJsonCodec. Without these, the generated
code that wraps types in Option or Seq fails to compile because no implicit
codec is in scope at the call site.

@lbialy @flsh86

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---

Summary by cubic

Add generic JsonValueCodec for Option[A] and Seq[A] in JsonSupport for scala-sttp4-jsoniter. This fixes compile errors in generated clients when optional or sequence fields are present.

• Bug Fixes
  • Provide given instances for JsonValueCodec[Option[A]] and JsonValueCodec[Seq[A]] via deriveJsonCodec, ensuring required implicits are always in scope.

^{Written for commit 8e59584. Summary will update on new commits. Review in cubic}

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}

[wing328]

thanks for the PR

cc @clasnake (2017/07), @shijinkui (2018/01), @ramzimaalej (2018/03), @chameleon82 (2020/03), @Bouillie (2020/04) @Fish86 (2023/06)

[wing328]

@reynaldjoabet are you using this change in your production environment to confirm it works for your use cases?

[wing328]

Is there a minimal spec to easily reproduce the issue and confirm the fix?

That will help speed up the review and get it merged sooner