Story

As a user of RHDH, I want to install a plugin that can show a custom header.

The initial use case will be the header that is created in Epic RHIDP-5125 / https://github.com/redhat-developer/rhdh-plugins/tree/main/workspaces/global-header/plugins/global-header

For this we should create a new mount point in rhdh that loads one or multiple header components.

They could be rendered one after the other one. It might be useful to have also here an optional priority if two headers are displayed. (See Jira headers where we almost always a header with the icon and some dropdowns and then this "notification bar", which you could also see as an header.)

The mount point should have also a configuration that allows the plugin to add the header to

1. the site (above everything, incl. the sidebar) OR
2. into the content area (above the content, but the sidebar is on the left)

The first one could be used in the future for maintenance notifications or if a customer likes to change our header position.

The second one is what we currently plan to use for our header.

We should expect that a header component crashes. So each header should be wrapped with a error boundary.

Background

Some technical notes: https://docs.google.com/document/d/1PdHmqMvGXlClYHVvuPhNaRVGQT_WqtrFNeRHgI6oQRk/edit

Dependencies and Blockers

QE impacted work

Documentation impacted work

Acceptance Criteria

1. Mount point definition and documentation
2. Header mount points are render in two different spots (above everything and just above the content)
3. Multiple headers are supported and each header is wrapped in an error boundary

There will be another ticket for e2e tests.