feat: Mini Apps

They are cool, but they are also relatively difficult to build. The grammY docs can build a bridge from novice programmers to advanced web tooling by providing a step-by-step guide that introduces all the necessary features and explains things along the way.

The official Telegram docs are more of a reference, or an explanation for experienced programmers. There is a lot of potential to boil it down.

This will have to wait a while until we had time to gain some experience building mini apps ourselves. It does not make sense to explain anything while we're still learning how to use them ourselves.