Add warnings during check file actions

[jeremypw]

To be used to investigate #2658

Not for merging.

[teamcons]

Quick question, how can i revert from this to the "standard" files once done?

In the past i had some issues, apt install --reinstall 'ing the official package would not seem to be enough to go back to an "official" version

[jeremypw]

@teamcons This branch only contains additional warning output added to the current 'main' branch. If you want to return to the latest daily version then checkout the main branch then rebuilld and install that (which is what I do as I am on the daily version of elementary)

If you want the current stable release version then first uninstall this branch with sudo ninja uninstall. You can then install the released version using sudo apt reinstall pantheon-files. Instead of using reinstall it may be better to use sudo apt purge pantheon-files followed by sudo apt install pantheon-files.

Alternatively you can build and install the released version yourself with

git fetch --tags
git checkout 7.2.0

Delete the build directory and then run the usual build and install commands.