Create Godot Meta Toolkit Demo Project

[devloglogan]

Update the demo project of the repo to showcase a few features of the platform SDK

• Achievements (Simple, Count, Bitfield)
• Downloadable content (Free DLC containing text to display)
• Display bidirectional followers that also own the app
• Display user name / profile image
• Display SDK initialization status and user entitlement status

[dsnopek]

Thanks!

I haven't tested this yet, but have just some initial comments from skimming the diff. I'll have more notes later after I test it :-)

[dsnopek]

I just tested, and this seems to work great! Just a handful of additional notes

[dsnopek]

Another thing I just thought of: we should put something in the documentation referring to this sample, so that folks know its there. My plan is to put the sample in the asset library as well, so we could mention/link that too (although, we won't have the link URL until after I publish it in the asset library).

[devloglogan]

Added a link to the demo directory from the getting started document. Once we have this app available on the store I figure we can link to that as well.

I've also added a readme for the demo project, which could also hold a link for the store entry when available.

[devloglogan]

I've removed the DLC example (and related permission request) and turned it purely into an IAP example where the label now just indicates if an in-app product has been purchased or not.

I've also enabled Quest 2 support.

[dsnopek]

Looks good to me!