Games the backend reports as streamable get a Play button. The player starts
a stream session, embeds the stream, and keeps the game's saves in
IndexedDB: sent when the session starts and updated as the server pushes
changes.
Games on other platforms (Java applets first) can be played through a
session manager that streams them from a server-side container. When
STREAMING_API_URL and STREAMING_API_TOKEN are set, game details and launch
data report whether a game is streamable, and POST /games/:id/stream-session
starts a session.
branderson