Align CI with Scala 2.13.9 and JDK 17

[dex-the-ai]

Summary

• align the GitHub Actions matrix with the repo's current Scala/JDK baseline by moving CI to Scala 2.13.9 on Temurin 17
• update actions/checkout and actions/setup-java to current major versions and use setup-java's built-in sbt cache
• replace the undefined panic shell path in the Couchbase startup step with exit 1

Verification

• JAVA_HOME=/usr/lib/jvm/java-17-openjdk-arm64 sbt test
• ruby -e 'require "yaml"; YAML.load_file(".github/workflows/ci.yml"); puts "YAML OK"'
• Launch the app on an alternate port to avoid an unrelated local :8080 conflict and verify the Swagger/CRUD path:
  • java -Dnetty.port=18080 -Dcouchbase.host=127.0.0.1 -cp <exported classpath> org.couchbase.scala.quickstart.Main
  • curl -L http://127.0.0.1:18080/docs
  • curl -X POST http://127.0.0.1:18080/api/v1/airline ...
  • curl http://127.0.0.1:18080/api/v1/airline?id=999001
  • curl -X DELETE http://127.0.0.1:18080/api/v1/airline?id=999001

Evidence

• tutorial-maintenance/runs/scala-quickstart/2026-06-02T0145Z/verification.md
• tutorial-maintenance/runs/scala-quickstart/2026-06-02T0145Z/sbt-test.log
• tutorial-maintenance/runs/scala-quickstart/2026-06-02T0145Z/screenshots/swagger-docs.png

Notes

• tutorial-maintenance/tutorials.json still described this repo's CI as Scala 2.13.8 on JDK 11; this PR brings the workflow in line with the existing build.sbt / README surfaces.
• The local list endpoint walkthrough hit Couchbase query-service bulk-get/KV timeouts to 127.0.0.1:11210 after the temporary CRUD pass. I left that behavior out of scope here because this PR only updates CI/workflow plumbing and the CRUD walkthrough itself still passed.
• I attempted to capture a short Swagger video as well, but only the screenshot artifact landed cleanly in this run.

Media evidence

• Auto-attached reviewer-facing media from the local verification artifacts captured during this run.
• This keeps the main PR body self-contained instead of relying on a follow-up comment for visual proof.

Notes

• Local artifact path: tutorial-maintenance/runs/scala-quickstart/2026-06-02T0145Z/screenshots/swagger-docs.png

[gemini-code-assist]

Note

Gemini is unable to generate a review for this pull request due to the file types involved not being currently supported.

[dex-the-ai]

Owner ping for this maintenance PR: @chedim

Requesting review from the manifest-listed owner(s) where GitHub does not already show a pending review request.