Prompt template version behavior on deploy
Key Takeaway
By default, a change set deploys every version of a prompt template, but nothing arrives active in the target org. A version that was ever active can no longer change, so you save changes to it as a new version.
A prompt template in Prompt Builder can have several versions, and each one is either a draft or published. When you move a template from a sandbox to production with a change set, settings in Setup decide which versions travel and whether they arrive active.
Draft and published versions
Prompt Builder supports multiple versions of one prompt template, so you can compare different prompt constructions and their responses. The first save creates Version 1. After that, choosing "Save As | Save as a New Version" creates the next version.
Each version is either a draft version or a published version. You can still edit a draft version. Activating a version changes its status from Draft to Published. A published version can never go back to draft.
Any version that was ever active stays immutable (it can no longer change), even after you deactivate it. To change it, save it as a new version.
A new version doesn't automatically become available to all users; you have to activate it first. If a template is in use, you can't deactivate a version unless another version is active, and you can't delete the active version.