- with frontmatter
  - input = own file content
- separate yaml file
  - input = content of file name with .yaml extension removed (if exists in patchset)
            OR target file content

- files without .yaml extension and without frontmatter overwrite/replace any files in the
  target directory (including mode)

- yaml !input or !target to select specific inputs from patchset/target tree (!input
  implicitly excludes file from being copied verbatim into target tree)

- processor input/(target, steal name from git diff source) keys for specifying
  primary/secondary processor inputs

- USE FS FOR INPUT FS AS WELL