[web] introduce UserProfileAvatarModal

Summary:
In this diff we introduce the UserProfileAvatarModal and we add an onClick callback to the user avatar which pushes this modal whenever the onClick callback gets triggered

This is step 4 in the list below
Outlined below are the steps I will take in this stack (each point here will be it's own diff):

1. Introduce FullScreenViewModal file and move everything from the ImageModal file into here, and change what is absolutely necessary (the imports)
2. Lift the rendering of mediaModalItem out of FullScreenViewModal
3. Finish renaming + updating remaining variables/callbacks to make FullScreenViewModal completly generic
4. Introduce UserProfileAvatarModal

Linear Task: https://linear.app/comm/issue/ENG-5202/introduce-fullscreenavatarviewmodal

Depends on D9497

Test Plan:
Please see the demo video below

Reviewers: atul, inka

Reviewed By: atul

Subscribers: ashoat, tomek, wyilio

Differential Revision: https://phab.comm.dev/D9498