[Feature]: Add Custom Navbar for custom menus and / or application headings

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Summary

Create a seperate header-section to enable application-wide custom menus (especially when using embedded mode) and / or application headings.

### Why should this be worked on?

When navigating through a multipage-app in embedded mode, currently the only way to add a (custom) menu is by using clickable elements like menu-buttons.

For consistency and a nice look & feel of applications I am using a container with a logo and menu-buttons along with the navigateTo-method for each multipage-app.

However this way one needs to clone this "pseudo"-menu-bar-header to each page and also edit it on all of the pages for any changes.

Retool has a seperate "header" section which "solves" this.

[Front conversations](https://app.frontapp.com/open/top_5r6bw)