Create a central entrypoint a JanusGraph server

**Describe the feature:**
Replace our default gremlin server startup with janusgraph management part.

**Describe a specific use case for the feature:**
* Add new GraphManager goal is to replace the cfg JanusGraphManager and the default tinkerpop with single and use this for any case.
* Add a new entry to start JanusGraph and ensure default configurations.

Start by examining the existing Gremlin server startup and the JanusGraph management configuration. Trace how GraphManager, JanusGraphManager, and the default TinkerPop setup currently interact. Done means a central JanusGraph server entrypoint replaces the default startup path and provides the intended default configurations.

Written by the indexing model from the issue text.