Deprecate websocket library

[haerdib]

ws-rs has not been updated for years and is now breaking the build on ubuntu-latest. As we have sufficient other websocket libraries (tungstenite and jsonrpsee), I suggest to deprecated the ws part, remove it from CI and later on remove it from the code completely.

Failing build: https://github.com/scs/substrate-api-client/actions/runs/12919440595/job/36029972296
Successful build, after downgrading Ubuntu: https://github.com/scs/substrate-api-client/actions/runs/12924234972/job/36042899472?pr=813

To solve this issue:

• Mark Wsclient library as deprecated
• Remove ws client example

[Niederb]

Yes, this library has not been updated in a long time.... Given that using another client is easy I think we can deprecate it 👍