Command-line entry-point for LSP features

### Describe the Bug

We'd like to experiment with a new command-line entry point for LSP. the primary intention of this would be for use in agentic skills, where a LLM can query pyrefly for semantic informatino about the program.

We would like to start with:
- find-references
- call hierarchy
- hover

The output of this should likely be json. Before merging, we'd like to experiment with real-world tools and test the effectiveness.

### Sandbox Link

_No response_

### (Only applicable for extension issues) IDE Information

_No response_