Are you currently part of the administrator group or an admin user?

It would be best if you debug your custom workflow instead of looking for ways to extract resources/nodes from segment id.

Check https://experienceleague.adobe.com/docs/experience-manager-cloud-service/content/headless/graphql-api/sample-queries.html?lang=en for CONTAINS operator.

Check https://experienceleague.adobe.com/docs/experience-manager-65/assets/content-fragments/content-fragments-models.html?lang=en for content fragment models

Can you try the same in vanilla  AEM 6.5.12 and AEM 6.5.16?

Can you share more details like Java, maven archetype, and maven versions?

Ideally, the Junit test case should not have any method which requires .jks. Junit is meant to mock your application code and test only the logic of your application.But, if .jks is still required, you should connect with Adobe Support Team.

Refer https://experienceleague.adobe.com/docs/experience-manager-learn/sites/translation/language-copy-feature-video-use.html?lang=en & https://experienceleague.adobe.com/docs/experience-manager-65/administering/introduction/tc-wizard.html?lang=en for language copy.

Check with the IMS org administrator (typically the same user who provisioned the environment via Cloud Manager) or Adobe Support Team for the access token.

You need to customize the accordion core component to set a limit of 20.Refer: https://github.com/adobe/aem-core-wcm-components/tree/main/content/src/content/jcr_root/apps/core/wcm/components/accordion/v1/accordion/clientlibs