Đế Gridfinity nesting kèm snap connectors cho A1 mini

This was created specifically for the A1 mini, as it has a bed of 180x180mm maximum.

With this change, you can print two 4x4 tiles of gridfinity base at once, saving 30 mins of printing time (54 min for one, 1.5h for two, in my configuration).

This is based on the work by @fldrmaus, which combines the nesting capabilities (printing multiple bases at a time) of @ChillChamp's original model with the snap connectors added by @Neel's remix.