[Feature] Collapse or hide the Appsmith header/bar by default on all pages

## Summary

Offer a configuration option for apps to show the header in a "collapsed" mode by default. For example, there could be a appsmith's logo in the upper right or left corner of the screen. When clicked, that square could open up and show the current full header and navigation.

## Motivation

Always showing the header with the full appsmith logo and the "Share" button is distracting. It takes up screen real estate. Marketing appsmith is completely ok, but I wish the header was a lot less intrusive.

## Additional Context

I know that "?embed=true" is a workaround. But I don't want to pass the query parameter across all pages.