fix(connect): avoid watch websocket read timeouts

[robinbraemer]

Summary

• Add a dedicated WatchService OkHttp client for the long-lived control WebSocket.
• Keep the existing Connect auth and metadata interceptors on watch requests.
• Disable the idle read timeout for the WatchService WebSocket and enable 30 second WebSocket pings so dead connections are still detected and recovered.
• Use synthetic platform metadata in the regression test so it does not look tied to a current Minecraft/Paper version.

Context

Some servers were reconnecting with java.net.SocketTimeoutException: timeout (cause: java.net.SocketException: Socket closed) while WatchService was under pressure. The server side saw context canceled during auth/session setup after the client closed the WebSocket request.

A normal OkHttp read timeout is a poor fit for an idle long-lived WebSocket because no session proposal may arrive for a long time. The safer pairing is no idle read timeout plus WebSocket pings; OkHttp cancels the WebSocket and notifies failure if a pong is not received for the ping interval.

Test Plan

• ./gradlew :core:test --tests com.minekube.connect.module.CommonModuleTest