🎨 [#1132] Add select-caret and filters for contacts

[jiromaykin]

select tag needs arrow/caret
https://taiga.maykinmedia.nl/project/open-inwoner/issue/1132

After discussing with Roxanne (designer):

• translation/textually "soort contact" and "type contact" should be the same; so pick one and use consistently (TODO later in translations), either use "soort contact" everywhere, or use "type contact" everywhere.
• align the Select element to the right
• add icon with expand_more arrow/caret
• discuss with designer if all filter-pages should look consistent
• delete the old PR/branch due to mess with merge-conficts, translations and wrong name.
• refactor Filters section to look more like all the others (like in Plans and Actions)

• Today I just found out that these filters should only be visible in the ‘Begeleider’ view, but for now I'll just make it look like all the other filter-views that we have. + Adding a Search field would be a task for later future.

[jiromaykin]

Because I'm surrounding the Contacts section with a Div, I had to indent the code inside; hence why it looks like there is a lot of 'new' code.

@vaszig and @Bartvaderkin : this is a new, clean branch of the issue that was approved last week, but without the crazy merge-conflicts and translation errors, so feel free to review this one again.

[vaszig]

We mainly use &__filter format and not again the whole name (like you do with &--open modifier) in the project, just mentioning for future updates. Same below.

[Bartvaderkin]

For the future: selecting up with a .parent.parent type of lookup is generally not a great pattern. It's better to select the outside first and then grab sub-parts, or use a real selector.