docs: Quickstart cleanup

[rube-de]

This PR

• removes truffle
• makes initial setup clearer
• changes diff to normal clodeblock with highliting for better copy

our prism dark theme, which is applied on the code-blocks, isn't the best visible. Maybe we could change from dracula to vsDark

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[aefhm]

our prism dark theme, which is applied on the code-blocks, isn't the best visible. Maybe we could change from dracula to vsDark

Agree.

[matevz]

Don't forget to squash before merging.

Also, please rebase the PR on the latest main branch instead of merging main changes into your PR.

[rube-de]

our prism dark theme, which is applied on the code-blocks, isn't the best visible. Maybe we could change from dracula to vsDark

Agree.

alternative, we could set

[data-theme='dark'] span.token-line.theme-code-block-highlighted-line span.token.comment { 
color: /*somthing better visible like greenish*/
}

to change the color of the highlighted comment

[aefhm]

alternative, we could set
[data-theme='dark'] span.token-line.theme-code-block-highlighted-line span.token.comment {
color: /somthing better visible like greenish/
}
to change the color of the highlighted comment

I'm open to any of these. I think the highlighting you introduced already is a lot better.