Add Connect API Service

[robinbraemer]

• Add Connect API proto client using connect.build (the same name is coincident)
• Move API protos from https://github.com/minekube/connect to moxy (watch, connect service)
• Use Buf's new Maven Package Repository for Java/Kotlin
• Add docs about using Connect API Service with Java/Kotlin using JitPack
• Document Super Endpoints in docs
• Test with a demo spigot plugin
• Ensure fetching connect-java api dependency from JitPack works https://jitpack.io/#minekube/connect-java
  • see https://github.com/jitpack/gradle-modular/blob/master/build.gradle
  • https://github.com/plan-player-analytics/Plan/blob/master/jitpack.yml

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• In a new PR migrate Guice to https://github.com/google/dagger