[FEATURE] Manage user email subscriptions from IBF

[arsforza]

Who requested this feature?

@arsforza @gulfaraz

User Story

As a IBF dev / manager
I want to move the user email subscriptions from Mailchimp to IBF
So that I have a more centralized way to manage portal access, and email / WhatsApp subscriptions

What needs to be done

• Create a new user-subscription table with the following columns:
  userId, country, disasterType, portalAccess, triggerEmail, whatsapp
• Update the user creation endpoint
• Create a new service to manage emails to send to mailchimp
• Create an admin page to manage subscriptions