Add permission to allow or block editing contacts in webapp

[dianabarsan]

What feature do you want to improve?
There is no way to block showing the edit button on contact detail pages, apart from blocking all writes by removing the can_edit permission.

cht-core/webapp/src/ts/components/actionbar/actionbar.component.html

Line 247 in 91c9349

<a mmAuth="can_edit"

For reports, we have a specific permission can_update_reports that gets checked along with can_edit in webapp actionbar.

cht-core/webapp/src/ts/components/actionbar/actionbar.component.html

Line 149 in 91c9349

<a class="mm-icon mm-icon-inverse mm-icon-caption" *ngIf="actionBar?.right?.type === 'xml'" mmAuth="can_edit,can_update_reports" [routerLink]="['/reports', 'edit', selectedReportDoc?._id]">

Describe the improvement you'd like
Add a can_edit_contacts permission, to mirror can_update_reports.

Describe alternatives you've considered
We could fine-tune this and somehow check individually for each contact, possibly by adding permissions to contact edit forms?

Additional context
Forum request