gui(installer): change collapse icon from left arrow to righ arrow

[pythcoiner]

Fixes #1416

[jp1ac4]

I wonder if the arrow should be on the left-hand side, i.e. > Advanced settings ?

[pythcoiner]

gpt is not helpfull:

Typically, the placement and orientation of the arrow in a collapsible menu follow certain design patterns for clarity and usability:

Position Relative to Menu Name:

Before the Menu Name: Common in more structured or hierarchical designs where it visually indicates a nesting structure, with the arrow on the left side.
After the Menu Name: This is more common in modern and minimalist designs. It provides a cleaner look and often aligns with the natural reading flow (left to right in Western cultures).
Orientation of the Arrow:

Right-pointing Arrow (►): Often used to indicate a menu that is collapsed or has hidden content. Clicking would open it to reveal more.
Downward-pointing Arrow (▼): Used to show that the menu is expanded, indicating that clicking it again will collapse or hide the items.
Examples:

Left of the Menu Name, Right-Pointing: Often seen in file explorers or hierarchical menu structures.
Right of the Menu Name, Right-Pointing/Downward-Pointing: Common in websites and web apps for dropdown menus or expandable lists.
Recommended Practice
For a straightforward user experience, place the arrow after the menu name and use a right-pointing arrow for collapsed menus and a downward arrow for expanded menus. This approach is familiar to most users and works well across devices.

@nondiremanuel we need your advise

[nondiremanuel]

I've seen it used in both ways so I think it's up to what we prefer.
Since we will need to edit the "Advanced Settings" again in the future as part of the general UX/UI improvement (it is not clear rn and it only contains the segwit vs taproot choice), I would do what's quickest / what you like most and not take too much time to discuss it.

[pythcoiner]

it's not really a big change, but if we change we should also maybe change at other places where collapse_icon() is used: