#2470: Add service server/client POC

[Hiepiscus]

This PR fixes #2470

Implements a minimal PoC for a background service with read-only access to URL metadata and a client that delegates requests to it when the service is running, while falling back to local resolution otherwise.

Implemented changes:

• ide service-server
• ide service-get-version
• IdeServiceServer
• IdeServiceClient
• IdeServiceProtocol
• Request, Response, Operation

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Testing instructions

1. Open two terminals and run ./build-local.sh in both.
2. Start the server using ide service-server.
3. If you want to verify that the URL metadata is loaded, run ide --trace service-server.
4. Verify that the server is listening on a port.
5. In the second terminal, run ide service-get-version , for example ide service-get-version java.
6. Verify that the latest version is returned.
7. Stop the server and run ide service-get-version again.
8. Verify that the output is the same as when the server was running.

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