Move generated translation files to res://.godot/translations

[aaronfranke]

Describe the project you are working on: A project with translations.

Describe the problem or limitation you are having in your project:

The problem is that these *.translation files are generated by Godot and therefore don't need to be committed to a Git repository. Currently users can ignore these files, but this isn't ideal, as described in the next section.

Describe the feature / enhancement and how it helps to overcome the problem or limitation:

With Godot 4.0, we will have the .import/ folder and the .mono/ folder moved inside of a general-purpose .godot/ folder, done in godotengine/godot#38607 and godotengine/godot#38704. The idea is that we should also use this folder to store generated translation files, so that you can ignore a single folder, .godot/, and have all generated files in Godot 4.0 be ignored.

Describe how your proposal will work, with code, pseudocode, mockups, and/or diagrams:

Branch: https://github.com/aaronfranke/godot/tree/translation-dotgodot

PR: godotengine/godot#42392 (see here for specific implementation details)

The above PR moves the generated .translation files into a subfolder of res://.godot called res://.godot/translations.

Note that projects need to be manually updated, since project.godot explicitly references the translation files. For example, the translation demo contains the text res://text.en.translation in project.godot.

If this enhancement will not be used often, can it be worked around with a few lines of script?:

Having *.translation in the gitignore will prevent them from being committed, which is the most important part, though they are still visible in the file browser when they don't really need to be. So this can be mostly worked around with a single gitignore line.

Is there a reason why this should be core and not an add-on in the asset library?:

Translation files are generated by the core engine, so where they go is a core feature.