chore: Move Linux-only configs out of "common" and into "linux"

common/.config/kate/externaltools/Rust%20Fmt%20Full%20File.ini

@@ -1,14 +0,0 @@
-[General]
-actionName=externaltool_RustFmt
-arguments=%{Document:FileName}
-category=Tools
-cmdname=rustfmt-full-file
-executable=rustfmt
-icon=text-x-rust
-mimetypes=text/x-rust
-name=Rust Fmt Full File
-output=Ignore
-reload=true
-save=CurrentDocument
-trigger=None
-workingDir=%{Document:Path}