docs: streamline getting started section (gnolang#5746)

The home page (`docs/README.md`) had a "New here?" intro paragraph
linking to Getting started / Quick Start / Installation: but those three
already appear as cards in the "Build on Gno.land" section (and in the
sidebar), so it was duplicated and not at the right place.

The inline bold links also rendered as broken full-width blocks on
docs.gno.land, since the home card CSS turns every link/`strong` into a
block.

This removes the intro paragraph so the home stays consistent with the
sidebar (Use / Build / Resources) and the right UX user journey. The
three pages remain discoverable under "Build on Gno.land".

Author: alexiscolin

docs/README.md

@@ -7,12 +7,6 @@ Gno.land is a smart contract platform built on a novel interpretation of Go
 decentralized applications with a minimalist approach and excellent developer
 experience.
 
-New here? Start with **[Getting started](builders/getting-started.md)** — the
-shortest path from zero to a working local chain and your first on-chain
-transaction (install included). Already comfortable with Go and just want
-the commands? See **[Quick Start](builders/quickstart.md)**. Need Docker, a
-source build, or a specific version? See **[Installation](builders/install.md)**.
-
 ## Use Gno.land
 
 Start exploring and using Gno.land. Setup essential tools, interact with the