* Fix home container height
The home container element's height was not set, so the lower half of
the home component was showing as the wrong color when the user had no
transactions or tokens.
This was broken in #8271, which was a fix for a different CSS problem.
Both problems should remain fixed now with height being set explicitly.
* Remove obsolete `flex` rule
This element is no longer within a flex container as of #8271, so this
rule doesn't do anything.
Two tabs have been created on the home screen: 'Assets' and 'History'.
This tabbed view is shown only on small screens (e.g. in the popup).
The fullscreen view is unchanged.
The toggle-able left sidebar no longer exists, so some 'sidebar-left'
specific code and styles have been removed. The button in the menu bar
has been removed as well.
The 'History' title of the transaction history is now redundant when
where are no pending transactions, so it as been conditionally hidden.
A passthrough for `data-testid` has been added to the Tab component for
convenience in e2e tests.
The "Transaction View" component has been merged with the Home
component. The division between these two components seemed wrong
because the "Transaction View" contained the menu bar (distinctly a
"home" thing, not a "transaction" thing), and we will be adding more
non-transaction-related components shortly.
This also let us use a single `Media` component instead of two.
The styles used for the Home component were in the huge
"newui-sections" SCSS file. Instead they've been moved into an SCSS
module alongside the component, to follow our conventions.
The `main-container` class was left as-is because it is shared between
here and the settings page.
