Refactor mobile chat into modal (#3038)

* feat(mobile): refactor mobile chat into modal

- Make page always scrollable
- Move mobile chat into a standalone modal

* fix(test): split out mobile browser test specs

* fix(mobile): force chat button to render on top of footer

* fix: some small updates from review

* fix: hide/show hide chat menu option based on width

* fix: chat button icon getting cut off

* chore(tests): add browser tests for mobile chat modal

* chore(tests): add story for ChatModal component

* fix(test): quiet shellcheck

* fix: remove unused import

* fix(tests): silence storybook linting warning

* fix(ui): reposition chat modal button icon with transform

web/components/layouts/Main/Main.tsx

@@ -171,11 +171,9 @@ export const Main: FC = () => {
           <FatalErrorStateModal title={fatalError.title} message={fatalError.message} />
         )}
 
-        {(!isMobile || !online) && (
-          <div className={styles.footerContainer}>
-            <Footer dynamicPaddingValue={dynamicFooterPadding} />
-          </div>
-        )}
+        <div className={styles.footerContainer}>
+          <Footer dynamicPaddingValue={dynamicFooterPadding} />
+        </div>
       </Layout>
       <Noscript />
     </>