Chore: Migrate App/index.tsx to hooks

[reinaldonetof]

Proposed changes

Migrate the App/index.tsx to hooks.

This is the second file, after the index.js. Here we start with a lot of providers, the redux and some modals.

Issue(s)

How to test or reproduce

• Test the themes, change them to another, and back
• Test the deeplink
• Test when dimension changes
• Test the tablet
• Test the theme in share extension

Screenshots

Types of changes

• [ ] Bugfix (non-breaking change which fixes an issue)
• [ ] Improvement (non-breaking change which improves a current function)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Documentation update (if none of the other choices apply)

Checklist

• [x] I have read the CONTRIBUTING doc
• [x] I have signed the CLA
• [x] Lint and unit tests pass locally with my changes
• [ ] I have added tests that prove my fix is effective or that my feature works (if applicable)
• [ ] I have added necessary documentation (if applicable)
• [ ] Any dependent changes have been merged and published in downstream modules

Further comments

Jira: NATIVE-45

[liversonp]

Hello. I was reviewing about hooks in react native and I found this way to hook consts using usereducer, I think this can help in clean code

• https://pt-br.reactjs.org/docs/hooks-reference.html#usereducer