JetBrains: Improve search result UI/UX

Created by: philipp-spiess

Closes #36703 (closed)

I’m sorry that all of the changes are inside one commit but these were very intertwined (and I, again, haven't thought about this until after I have touched too many files )

This basically applies the Figma designs for all search result types to our component structure. I'm explaining all the changes in more detail in the Loom.

It also fixes an issue where calling event stream polyfill in a browser (like we do here inside Chromium) breaks our tooltip library. The reason for that is that it also polyfills window.Event, even though browsers support that already and it is not necessary to do for only applying headers properly. I've slightly changed the polyfill code to use native Event and MessageEvent which seems to work fine for me! (cc @tjdevries)

In the video I mention two issues which I checked against main to not be regressions. Created follow-up tasks for that:

• #36812 (closed)
• #36813 (closed)

Test plan

Manually tested:

https://www.loom.com/share/6ba6f9a04f634ccc8f763b41bf36208a

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.