[Feature Request Review]: LSP support with JSON-RPC communication for type information on hover

Hey,
I really enjoy plannotator since day one. The added reviewer is especially a great step in managing agent output. What I'm missing most in reviewing code is the abilty to reason about types and interfaces and how they interact in the changes. Not having this information in the review forces me to constantly switch back and forth between plannotator and my IDE, because I'm lacking the context of the change and how it affects the overall system.

Is adding LSP support something you'd be interested in? I'd be happy to work on that (with your input on a few system design decisions).

As a first PoC we could limit the usage to typescript and type info on hover. An iteration of that could be clicking into another type of the hover and resolve that type.

My first idea is:
- You open a review
- Plannotator detects the used language
- Plannotator checks if a LSP is already available
- If not it prompts a install toast
- If yes, it starts the LSP lazily while the review UI opens and injects the hover functionality into the Pierre Diff