[Console] Tweak the tree helper

[javiereguiluz]

This continues #20786 to do some minor tweaks.

1. We now display a full example of how to select the built-in styles.
2. The listing of built-in styles now provides more details.

Before, it was rendered like this (see https://symfony.com/doc/7.3/components/console/helpers/tree.html)

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I think it's fine to remove the :method: link because it doesn't provide direct links to the method, just to the class. So, all the previous :methods: links were in practice the same link.

[OskarStark]

Like it

[OskarStark]

Thank you Javier.