In accordance with #30327, I saw no reason for included files to get
special treatment, and I actually get use out of prefilling excluded
files because I like not to search symlinked files which, in my
workflow, use a naming convention.

This is simply implementing the same exact changes, but for excluded. It
was tested with `"space /": ["pane::DeploySearch", { "excluded_files":
"**/_*.tf" }]` and works just fine.

Release Notes:

- Added `excluded_files` to `pane::DeploySearch`.