[edit] version/changelog [up] to release Simplify.Web.Json 2.4.2

- Bump target framework from net6.0 to net10.0
- Upgrade Simplify.Web dependency from 5.1.0 to 5.3.0
- Update TesterApp to net10.0
- Update GitHub Actions: checkout@v6, setup-dotnet@v5,
  upload-artifact@v7 with explicit dotnet-version 10.0.x
- Update README platform badge to .NET 10.0

[edit] version/changelog

[fix] formatting

[edit] to controller v2 examples

[add] postman environment

[edit] version/changelo

[edit] version/changelog

[edit] version/changelog

[fix] .NET 5 obsolescence warning

[add] Explicit .NET 6 targeting

[uo] Simplify.Web bump to 4.6
[r] file-scoped namespace, latest lang
[del]explicit output folder

[edit] version/release notes