NEVER_DERIVED

Paths that are never derived, whatever any other rule says: they decide what is derived, so they always merge as text. Checked before every other rule.

Pattern	Why
`lvcs.toml`	declares the generator's `writes`, `run`, and `inputs`
`**/.gitignore`	decides which files sync, and so which are inputs
`**/.lvcsignore`	decides which files sync, and so which are inputs
`**/.gitattributes`	marks files derived