Enhancement: Dedup Using White/Black List

We would like to have an option to use one process which uses a single config directory but can exclude or include certain files.
Our aim is to have one process with a granular control of which CTMPL is deduped and which is not.

The issue names no files, tests, or entry points. Start by locating how the single config directory is processed and how CTMPL files are selected for deduplication; done means one process can include or exclude files with granular control.

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