Add setBlurredBackground command to external api.

Co-authored-by: Axel Prola <axel.prola@equasens.com>

Some middleware functions are declared as async. This wraps next(action) in Promise which will delay the execution of actions and also dispatch will return the its result always as a Promise.

Currently if a button in the main toolbar is not visible, the button is
not replaced by another button from the overflow menu.

Since plan-b mode will no longer be supported, check for unified plan support is not needed anymore.

* New config disable feature virtual background

* Change enableVirtualBackground to disableVirtualBackground in config file and correct lint problems

* Fix comment disable virtual background

* Change deprecated APP.storage to IReduxState

Move visible logic inside each button
Move click functionality inside each button
Extract getButtons function from Toolbox components to functions file

feat(a11y): Globally improve accessibility for screen reader users

Use correct types for action, dispatch and getState

Upgrade eslint related packages
Fix new errors

In the case when the user selects a new video device then goes to Virtual Background without saving first, use the newly selected device for the virtual background preview instead of the saved one

Remove unnecessary @ts-ignores
Use @ts-expect-error instead of @ts-ignore for external dependencies

Move styles from SCSS to JSS
Convert a component from class to function

Fix some errors. Remove @ts-ignores
Convert some files to TS
Remove some eslint-disables

Remove unnecessary @ts-ignore
Fix some TS errors

Create Tooltip component
Fix Popover positioning calculations
Add margins to popover
Remove @atlaskit/tooltip
Update all components to use the new Tooltip component

Added tooltip actions and reducers for the following functionality: when a user hovers over an element is sees the tooltip for that element and then hovers another element that has a tooltip, instead of using the delay and animations we just unmount the current tooltip and mount the next one immediately

Replace atlaskit Spinner with the new component
Remove @atlaskit/spinner

Implement redesign

Even when images are provided via dyamic branding.

Fixes: https://github.com/jitsi/jitsi-meet/issues/12941

* tss-react doesn't need a type anotation for the Theme

* Update tss-react to 4.4.4

Remove unused icons
Remove fill none from icons
Rename some icons

Remove global variables from files
Change type to interface

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

Convert some files to TS

Its no longer supported in multi-stream mode.

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

Remove unnecessary ts-ignores
Change any to actual types
Fix eslint rule

Create IStateful interface
Use IState interface everywhere
Remove unnecessary @ts-ignore

Convert files that use material-ui to TS (needed for material-ui upgrade)

Found via `codespell -q 3 -S ./lang -L miliseconds`