feat: assets folder for metainfo.xml and .desktop files

[Owen-sz]

This adds the assets folder and files discussed in #185. Will get started on a PACKAGING.md soon.

The metainfo.xml file will be used by Terra, and can be used for a Flatpak/any other repo that supports AppStream metadata.

The .desktop file should be used by all packages going forward.

A few questions/comments

• Not sure if 'Snow' should be uppercase here, I assumed yes
• Is twvd good for the developer name?
• Is there a better screenshot description?
• Are there any other URLs we'd want to link?
• Are there any other keywords?

Here is a preview of what a GUI software store would look like showing Snow (note this image is missing the developer and screenshot):

Also, I'm thinking of moving the app icons to this assets folder, this owuld be easier for packagers but would lead to fragmentation since the other images in docs/images don't need to more. Other option is to put these other images in a assets/screenshots or something folder.

[twvd]

Hi, thank you for this :) I like the idea of packaging Snow as flatpak as well, that would ease the pain of maintaining many different distro packages.

As for your questions:

• Yes, Snow should start with a capital letter (also the title in your screenshot)
• You can use "Thomas W." as author as I put that also in the about dialog
• In the README and website there's a screenshot of Snow running a Mac II with some debug dialogs open, I think that works.
• The main website should be in there: https://snowemu.com/. You can also refer to the docs in the description: https://docs.snowemu.com/
• I agree it makes more sense to move the icons and other images unrelated to the docs to assets. Feel free to do so.

Please let me know if you need anything else!