TechDebt: Merge Prune & Delete code & names

Delete and Prune are used to mean the same thing. I think we should combine all the prune code into the delete code. This would reduce complexity and code to maintain. AFAICT their behavior is identical.

No files, tests, or entry points are named. Start by locating the prune and delete implementations in the cli-utils codebase, then compare their behavior and call sites before determining the scope of consolidating the two concepts; done means the duplicate prune code and naming are removed without changing behavior.

Written by the indexing model from the issue text.