fix(DIAM-12): Add validation for Collector Profile location city

[lilyfromseattle]

The type of this PR is: FIX
@artsy/diamond-devs

This PR solves DIAM-12

Description

The location input field on collector profile doesn’t have any kind of validation, meaning it takes anything
The placeholder says City, but the user can ignore the autocomplete and enter anything
This leads to weirdness on areas where collector profile locations is surfaced (demand, convos, etc)
Let’s add validation to that form, so we ensure it always corresponds to a valid city.

Before:
https://github.com/user-attachments/assets/603f3ef3-942a-4b60-98ab-840b8be7af39

After:
https://github.com/user-attachments/assets/079b73ce-e6ad-4c32-99cf-b92486499d5e

[relativeci]

#4612 Bundle Size — 9.51MiB (+0.03%).

fd03aea(current) vs 3308081 main#4605(baseline)

Warning

Bundle contains 35 duplicate packages – View duplicate packages

Bundle metrics   1 change

	Current #4612	Baseline #4605
Initial JS	3.74MiB	3.74MiB
Initial CSS	0B	0B
Cache Invalidation	43.79%	41.06%
Chunks	102	102
Assets	105	105
Modules	6073	6073
Duplicate Modules	590	590
Duplicate Code	4.35%	4.35%
Packages	298	298
Duplicate Packages	34	34

Bundle size by type   1 change 1 regression

	Current #4612	Baseline #4605
JS	9.37MiB (+0.03%)	9.37MiB
Other	144.3KiB	144.3KiB

Bundle analysis report Branch lilyfromseattle/cp-city-validati... Project dashboard

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[anandaroop]

This may cause problems for some edge cases for cities with weird location hierarchies (not even all that edgy: try Brooklyn, NY), but as long as we accept that, lgtm.

[lilyfromseattle]

This may cause problems for some edge cases for cities with weird location hierarchies (not even all that edgy: try Brooklyn, NY), but as long as we accept that, lgtm.

fml