jvm -> scala version in sbt, not yml

[lrytz]

No description provided.

[Copilot]

Pull request overview

This pull request refactors the build configuration to move Scala version selection from GitHub Actions workflow files into the sbt build definition. The change introduces a Java version-based approach where the build automatically selects appropriate Scala versions based on the Java runtime version being used (Java 8 vs Java 17+).

Changes:

• Introduced java8or17 helper function to conditionally set Scala versions based on Java runtime
• Consolidated build settings into commonSettings sequence applied to all projects
• Simplified CI and release workflows by removing explicit Scala version matrices and using sbt's native cross-building commands

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
build.sbt	Added Java version detection logic, consolidated common settings, updated Scala version variables (scala3 → scala3_3, added scala3_8), and applied dynamic crossScalaVersions configuration to all projects
.github/workflows/release.yml	Simplified from separate jobs for core/cli and sbtplugin to a single unified release job using ci-release
.github/workflows/ci.yml	Removed explicit Scala version matrix, replaced with +test and +sbtplugin/scripted for cross-version testing

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