Real-time flags - hashed identity updates

[dabeeeenster]

If the state of an Identity changes, we want to send a message to that specific identity to refresh their flags. The issue is that we only have environment level granularity with SSE messages.

Proposed solution is to send a hashed identity string to all of the connected clients for that environment. They then check to see if it matches their own hash calculation. If it matches, they refresh their flags. This obfuscates the identities to other clients.

Trigger this whenever an identity state change takes place.

[dabeeeenster]

This logic will need adding to all real time sdks