Cut legacy-upgrade welcome dialog #1927
Description
When the user first opens this app, if it was installed as an upgrade from the legacy Zulip mobile app, we show a brief welcome dialog about the new app.
As of today, it's four months since the new app was launched (on 2025-06-17). The dialog is probably still appropriate, for the trickle of users still upgrading from the legacy app.
Eventually, though (perhaps after a year?), the wording of the dialog might feel stale and it might make more sense to just get on with things, with no such dialog.
References
- Original issue for welcome dialog: Show a welcome dialog on upgrading from legacy app #1580