clio should have a config field type that has to be a path, and it should expand homedir etc.

**What would you like to be added**:

Clio should know that certain config fields represent paths on the local filesystem, and should do some common expansions, for example `~`, `$HOME`, and `$TMPDIR`, so that these can be expanded.

Probably we want something like `type LocalPath string` in the config, and then config structs in clio applications can declare fields to be `LocalPath` instead of `string` in order to get the expansion behavior.

**Why is this needed**:

https://github.com/anchore/grype/issues/2024
https://github.com/anchore/grype/issues/2599

Start by reviewing clio's configuration handling and the related grype issues #2024 and #2599. The work is done when configuration fields can use a LocalPath type and common local filesystem values such as ~, $HOME, and $TMPDIR are expanded.

Written by the indexing model from the issue text.