Remove global variables from files
Change type to interface

Remove ts-ignores that are no longer needed because of tsconfig.web.json
Change ts-ignore to ts-expect-error for files outside react/features

Remove unnecessary ts-ignores
Remove unnecessary eslint-disable
Fix type errors
Change Dispatch type to IStore['dispatch']

Use new TS config from @jitsi/eslint
Fix all lint errors

* fix(audio-only) Do not enable video automatically when audio-only is disabled.

* language(typescript) first ts component, added ts configurations, actionTypes.js are now ts files

Up until now we relied on implicit loading of middlewares and reducers, through
having imports in each feature's index.js.

This leads to many complex import cycles which result in (sometimes) hard to fix
bugs in addition to (often) breaking mobile because a web-only feature gets
imported on mobile too, thanks to the implicit loading.

This PR changes that to make the process explicit. Both middlewares and reducers
are imported in a single place, the app entrypoint. They have been divided into
3 categories: any, web and native, which represent each of the platforms
  respectively.

Ideally no feature should have an index.js exporting actions, action types and
components, but that's a larger ordeal, so this is just the first step in
getting there. In order to both set example and avoid large cycles the app
feature has been refactored to not have an idex.js itself.

React Native doesn't define __filename nor __dirname so do it artisanally. In
addition, this helps with centralizing the configuration passed to loggers.

This refactors all handling of audio-only and last N to 2 features in preparation
for "low bandwidth mode".

The main motivation to do this is that lastN is a "global" setting so it helps
to have all processing for it in a single place.