Redesign public profiles and toots (#8068)

app/controllers/concerns/account_controller_concern.rb

app/controllers/statuses_controller.rb

app/helpers/stream_entries_helper.rb

app/javascript/mastodon/components/relative_timestamp.js

app/javascript/packs/public.js

app/javascript/styles/application.scss

app/javascript/styles/mastodon/accounts.scss

app/javascript/styles/mastodon/basics.scss

app/javascript/styles/mastodon/components.scss

app/javascript/styles/mastodon/containers.scss

app/javascript/styles/mastodon/footer.scss

app/javascript/styles/mastodon/stream_entries.scss

app/javascript/styles/mastodon/variables.scss

app/javascript/styles/mastodon/widgets.scss

app/models/concerns/account_header.rb

app/views/accounts/_bio.html.haml

app/views/accounts/_follow_button.html.haml

app/views/accounts/_follow_grid.html.haml

app/views/accounts/_follow_grid_hidden.html.haml

app/views/accounts/_grid_card.html.haml