feat: Crisp integration for `crm/contacts`

Description

Adding Crisp chat integration to crm/contacts.

Few concerns

Crisp uses a separate subresource for contact's custom properties (they call it “custom data”). This brings several challenges when mutating the data in a single use case.

`Create` use case

first creates the general contact
- if that fails (usually the contact already exists), all is good, nothing in Crisp was changed, can be retried
then updates the contact's custom data subresource
- that fails, we have inconsistent data in Crisp. The new contact was created, but custom data was not set

I chose to fail the whole Create use case when custom data patch fails with a custom error describing the issue. No one will actually read the map and implement the special case, but:

they probably will retry the failed Create
since the contact will exist, it will return 404 (Already exists)
that should be switched to Update (generally)

Alternatively, we could simply not support this use case (like Mixpanel integration) and quietly create the non-existent resource in Update.

`Update` use case

first updates the general contact
- if that fails (404 or smth), all is good, nothing was changed, can be retried
then updates the contact's custom data subresource
- that fails, we have inconsistent data in Crisp. The contact was updated, but custom data was not set

This is much easier since Update is much more idempotent-ish. We simply fail the whole use case call and it can be safely retried, yielding the desired end result.

Motivation and Context

Types of changes

[ ] Bug fix (non-breaking change which fixes an issue)
[x] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

[x] I have read the CONTRIBUTING document.
[x] I haven't repeated the code. (DRY)
[x] I have added tests to cover my changes.
[x] All new and existing tests passed.

superfaceai / station