feat: limit add another to same geo level

[sgratzl]

closes #624

Prerequisites:

• Unless it is a hotfix it should be merged against the dev branch
• Branch is up-to-date with the branch to be merged with, i.e. dev
• Build is successful
• Code is cleaned up and formatted

Summary

limits the possible items in the add another search box to more of the same level, e.g. here states:

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[dlaliberte]

I'm not seeing this work entirely. If I first remove any counties, then when I switch to States, the completion list shows states, but otherwise, it continues to show counties. Same thing in reverse: if any states have been selected, after switching to Counties, it still shows states. If I have both counties and states selected, then counties override states in the decision of what to show. Seems like it should always show whatever is chosen in the "for ..." selector regardless what is currently selected.

[sgratzl]

atm the logic is that is shows more of the same. So, if you have selected a state (like Minnesota) it will list more states. If you have selected a county (like Allegheny County) it will list counties. There is no connection to what geo type one has selected in the map.

[tildechris]

I like how this works. I think I found a bug, however:

• Clear any selected region
• Go to "Region Details"
• Search and select "Allegheny County, PA"

The text Allegheny County is text repeated in the text field making it awkward to add the next region.

[sgratzl]

I like how this works. I think I found a bug, however:

* Clear any selected region

* Go to "Region Details"

* Search and select "Allegheny County, PA"

The text Allegheny County is text repeated in the text field making it awkward to add the next region.

should be fixed

[tildechris]

LGTM, thanks Sam.