Send notification to client with Push Notifications

Ref. PWA13.3

NOTE: this feature is from a big development. See PWA discussion at GitHub.

Is your feature request related to a problem? Please describe.

As a registered participant in Decidim that has given consent and permission to receive push notifications, I want to see the notification.

Describe the solution you’d like

I want to receive these notifications with the title, body, icon, and link when possible.

For these, what we’ll use:

• Title: Proposal is being evaluated
• Body: The "Possibility to configure default sorting for proposals" proposal is being evaluated.
• Icon: Organization Favicon
• Link: https://meta.decidim.org/processes/roadmap/f/122/proposals/13104

Describe alternatives you’ve considered

It’d be awesome to also show an image in the cases where there are images in the card (ie some Proposals, Meetings, BlogPosts, etc), but AFAIK this is not easily available in Decidim::Notification at the moment.

Additional context

See a demo of all the capabilities possibles to Notifications and see Display a notification in Google’s guide.

Notifications examples from OneSignal.com

Does this issue could impact on users private data?
It could have some personal data in some notifications (for instance, in the case of Messaging)

Acceptance criteria

• Given that I’m a participant that has been given permission to receive push notifications,
  When I get a new notification in /notifications
  Then I also receive it on my device
  and this notification has a title and body
  and has a link to the resource
  and has the icon of the organization.