Augment `to`/`from` address in activities

[onbjerg]

In order to easily query activities that belong to certain apps and/or organizations we need to augment the to and from properties of activity documents with some additional data.

Currently, these properties are a checksummed address, but a more suitable format would be:

interface AddressProperty {
    address: string;
    organization?: string;
    appId?: string;
}

Where organization is the organization that sent/received the activity, address is the specific sender/recipient (such as a voting app) and appId is the app ID of address in the case that the sender/recipient is an app.

Solving this task both involves persisting this data on an ongoing basis and creating a migration for old data. It also requires changes to the app score calculation task.

[onbjerg]

No longer in scope.