Outline appearance for Input components

## 🚀 Feature Proposal

This is mostly related to Eva Design System feature proposals. However, I would like to open it here to view the interest of other library users.

It would be nice to have another predefined stylings for Input and similar components configurable with `appearance` property.
Compared to Button, we may also have `outline` appearance in Input fields, to make its background color transparent (with respect to the transparency percentage of the design system).

## Motivation

1. Transparent Input backgrounds are useful on contrast backgrounds. See screenshot.


2. The only way to achieve transparency in Input fields is to use `control` status. However, using that value will make it impossible to use others like `danger` or `success` (which are quite useful within forms validation), leading to setting non-transparent white background color to Input when changing. Moving transparent stylings in additional appearance seems to be a solution for this case.

## Example

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