client fails with party ids other than `[0, 1, 2, 3]`

[matthiasgeihs]

The client accepts a parameter parties: number[], which it also forwards to the server. However, due to how the client maps between the provided party ids and the other parameters like endpoints and sockets, providing anything else than [0, ..., n-1], where n is the number of endpoints, fails.

The reason is that the party ids are used for indexing into the endpoints and sockets arrays, as can be seen here:

tss-client/packages/tss-client/src/client.ts

Line 63 in bb1a5d9

const socket = tss_client.sockets[party];

tss-client/packages/tss-client/src/client.ts

Line 431 in bb1a5d9

return this.endpoints[party];