Show the Orbit node sidebar below the indexing button

What does this MR do and why?

On the Orbit Overview, the "Indexing N projects" button covered the title and the close button of the node sidebar. Both sat in the top-right corner of the map.

• The button and the sidebar now share one column on the map. The sidebar opens below the button.
• When indexing finishes, the button goes and the sidebar moves up. When the button comes back, the sidebar moves down.
• On small screens, the button now shows on the map, not above it.

References

• Follow-up to !262214 (merged)

Screenshots or screen recordings

Local GDK in SaaS mode. The group status replies are set in the browser: 1 project indexing, then indexing done, then 2 projects indexing. The videos play at 2x speed.

Before	After
The button covers the sidebar title and its close button.	The sidebar opens below the button, moves up when indexing finishes, and moves down when the button comes back.

How to set up and validate locally

1. Turn on Orbit for a group with projects, and wait until the Group status tab shows the group as indexed.
2. Create a project in the group.
3. While the new project waits for code indexing, open /dashboard/orbit/overview and select a node on the globe:
   • On master, the "Indexing 1 project" button covers the top of the sidebar.
   • On this branch, the sidebar opens below the button.
4. Keep the sidebar open until the project is indexed. The button goes away and the sidebar moves up.

MR acceptance checklist

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