ci!: test on Java 17, 21, 25

[jGleitz]

BREAKING CHANGE: testfiles supports only Java >= 17 now

Upgrade to gradle 9 and adapt plugins and build to it.

fixes #201

[Copilot]

Pull request overview

This PR updates the CI workflow to test against more modern Java versions and switches to the Temurin distribution. The project targets Java 8 compatibility but tests against newer versions to ensure forward compatibility.

Changes:

• Replaces Java 16 with Java 17 (LTS) and adds Java 24 and 25 to the test matrix
• Updates JDK distribution from 'adopt' to 'temurin' (following AdoptOpenJDK's transition to Eclipse Adoptium)

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

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[jGleitz]

@copilot please see the kotlin java target version to v11 everywhere

[Copilot]

@jGleitz I've opened a new pull request, #195, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

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Copilot reviewed 12 out of 13 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

.github/workflows/ci.yml:96

• The Release Check step runs on pull_request events but relies on secrets.RELEASE_GITHUB_TOKEN. For PRs from forks this secret will be unavailable, which can cause semantic-release to fail and make CI red. Consider gating this job/step to push events only, or falling back to ${{ github.token }} (and/or running semantic-release --dry-run on PRs) so PR validation doesn't depend on privileged secrets.

  release:
    name: Release Check
    runs-on: ubuntu-latest
    needs: build
    steps:
      - name: Checkout
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6

      - name: Setup Node.js
        uses: actions/setup-node@6044e13b5dc448c55e2357c09f80417699197238 # v6.2.0
        with:
          node-version: lts/*

      - name: Release Check
        env:
          GITHUB_TOKEN: ${{ secrets.RELEASE_GITHUB_TOKEN }}
        run: npx semantic-release

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[jGleitz]

@copilot I was mistaken about the best flow for the CI. Please change the GitHub actions so that the docs are build and published only in the release pipeline. But please do it such that there's only on job in the release pipeline, not two. Pushing the docs to GitHub pages should happen only after the artefacts have been published successfully with Gradle.

However, the CI pipeline should still build the docs and publish them as an artifact on the run

[Copilot]

Pull request overview

Copilot reviewed 13 out of 14 changed files in this pull request and generated 3 comments.

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[jGleitz]

@copilot please improve the CI by running the release check only on main

[Copilot]

@jGleitz I've opened a new pull request, #200, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

Copilot reviewed 14 out of 15 changed files in this pull request and generated 3 comments.

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Pull request overview

Copilot reviewed 15 out of 16 changed files in this pull request and generated no new comments.

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