feat(scopes): add ScopesBridge

[tskarhed]

✨ Description

Related issue(s):

Closes #45

Enables Scopes usage. Inspiration taken from https://github.com/grafana/grafana/pull/97176/files#diff-ad37fab92c3cc711f1ba8ce84693e7c07543a93aaba842d1cc925d3bd6531b57

📖 Summary of the changes

• Instantiates a new ScopesBridge
• Use the ScopesBridge to enable the topbar
• Use ScopesBirdge to get scopes when making queries. This can't be done automatically, as the app is not structured around scenes.

🧪 How to test?

Enable feature flags and click around

[NWRichmond]

@tskarhed with respect to:

Use ScopesBirdge to get scopes when making queries. This can't be done automatically, as the app is not structured around scenes.

I'm assuming this refers to not using SceneApp, which wraps its own ScopesBridge? If so, I'll make note that we'll remove the ScopesBridge added here if we ever make the transition to SceneApp.