Intention dropdown in UI only includes local dc services

I have service `static-client` running in `dc1` and service `static-server` running in `dc2`. I want to create an intention between the two. I go to the UI and select `static-client` in the dropdown for "Source Service". When I click on the dropdown for "Destination Service" `static-server` doesn't exist. I need to type in the service name and as I type it says "Use a future service called 'static-server'". This is confusing because it's not a future service, the service already exists, just not in the current DC.


NOTE in the screenshot I've already created the intention so `static-server` now shows in the dropdown. It would usually look like:

It would be nice if the dropdown included services from all dcs *or* "Use a future service" was re-worded to account for other dc services.

Reproduce the intention-creation flow with services in different data centers and inspect the UI entry point that populates the Source Service and Destination Service dropdowns. Done means an existing service in another data center is represented correctly, or the fallback wording clearly distinguishes it from a future service.

Written by the indexing model from the issue text.