Store translations in a plugin
A gotcha with strings inside the language definition files:
The Languages section of a multi-language Kirby website has an interface for editing strings. Whenever the Panel user changes the value of one of the strings, the languages/<lang>.php file gets overwritten to include the updated string. This places using the visual editor at odds with syncing the site/languages folder during deployment.
The translations editor can be disabled with permissions attached to custom user roles. These don’t apply to the default Administrator role, so you’ll need to create a custom role for the other users.
Alternatively, you can move the translations to a place where they don’t interfere with the translations interface: a plugin that defines the translations key. You could move Panel translations into a plugin, as you might want to support languages for the Panel that you don’t necessarily want in the front-end.