multi-language: app string audit

[mattroe]

Do one pass before LA demo (less for LA demo more for initial user testing)

Find a translation vendor

Also provide HMPB strings for translation

[arsalansufi]

We've added vendor-generated Spanish translations, the vendor being https://www.translationshop.co: #4863

And used those translations for the VSAP LA demo.

Seems to have all gone well so will request Chinese translations soon and also document / iron out the process for getting these translations and loading them in.