Improvements to persisted state migration (#2098)

* Fix session email/emailConfirmed types, update usage for safer access

* Handle fallback better, better errors

* Better handling, add test

* Add test for default data

* Remove fallback, not needed, update logs

src/view/shell/desktop/RightNav.tsx

@@ -58,8 +58,8 @@ export function DesktopRightNav() {
                 type="md"
                 style={pal.link}
                 href={FEEDBACK_FORM_URL({
-                  email: currentAccount!.email,
-                  handle: currentAccount!.handle,
+                  email: currentAccount?.email,
+                  handle: currentAccount?.handle,
                 })}
                 text={_(msg`Feedback`)}
               />