chore: Group legacy tests under one navigation button

[kmichalikk]

Description

This PR reorganizes the Example app structure:

Warning

This PR DOES NOT update the navigation in e2e apps. Since they are currently not working anyways, we can redo them in a separate PR to make it easier to read in one go.

Before:

Start
|__ Settings (Dark mode, RTL)
|__ Examples
|__ Playgrounds
|__ ... TestXXXX ...
|__ Component Integration Tests
|__ ... TestXXXX ...
|__ Single Feature Tests

After:

Start
|__ Examples
|__ Playground
|__ Legacy Tests
|    |__ ... TestXXXX ...
|.   |__ ... TestXXXX ...
|__ Single Feature Test
|__ Component Integration Tests

Changes

• Moved issue tests (TestXXXX and TestBottomTabs, etc.) to separate directory and into another screen navigable by clicking a button. For this, the logic inside Example.tsx needed to be split into Example.tsx and tests/LegacyTestsScreen.tsx.

Test plan

Click through the example app & verify that the screens can be navigated to.

Checklist

n/a