[AGS] unknown game variant for 'ags-fallback' (Stellar Mess Demo)

[MarcoBorrini99]

The game in 'StellarMessDemo_WIN' seems to be an unknown game variant.

Please report the following data to the ScummVM team at
https://bugs.scummvm.org/ along with the name of the game you tried to add and
its version, language, etc.:

Matched game IDs for the ags engine: ags-fallback

{"StellarMessDemo.exe", 0, "a409703089eebbcfa13f0a22f6fb71ed", 8713074},

Extra Info:
Url: ​https://tibbagames.itch.io/stellar-mess
File: StellarMessDemo_WIN.zip (size: 1.790.943; md5: 3322b82d4dcd41396345661178e22a52)
Version: n/a
Language: Multi