Add quick start guide

[gamarin2]

Closes: #XXX

Description

Quick start guide using the latest scaffold tool

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[tac0turtle]

nicely written, but if we break or update the scaffold tool then we have to come here and update the docs. Maybe before this gets merged we put something in the readme of that repo to fix these docs when changing things

[gamarin2]

nicely written, but if we break or update the scaffold tool then we have to come here and update the docs. Maybe before this gets merged we put something in the readme of that repo to fix these docs when changing things

I think we should, because the scaffold guide will not only be used in the SDK docs, but also in the tutorials and maybe in other places. So definitely adding a list of content to update in the README of the scaffold repo is a good idea

[codecov]

Codecov Report

Merging #5517 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5517      +/-   ##
==========================================
- Coverage   54.22%   54.21%   -0.02%     
==========================================
  Files         313      313              
  Lines       18974    18974              
==========================================
- Hits        10289    10287       -2     
- Misses       7885     7887       +2     
  Partials      800      800

Impacted Files	Coverage Δ
x/mock/app.go	62.83% <0%> (-1.36%)	⬇️