Feature: Retrieve info about registered Resources and execute them from a tool

Problem

I think it would be interesting to be able to create tools that can see what resources have been registered and return their content or process it to improve the model context.

Solution

Server should have a method that returns an array with the metadata of the registered resources, as well as a method to execute them by name and/or uri and obtain their content.

Additional context

Make it easier for models to get their own context through tools, or obtain resource context to use with sampling in tools.

Workaround

let regResources = [];

let newResource = server.registerResource( ... );
regResources.push({resource: newResource, resUri: uri});

...

let resourceToCall = regResources.find(res => res.resource.name === resourceNameToCall);
let resourceContent = await resourceToCall.readCallback(URL(resourceToCall.resUri), extra);

Start with the server's existing registerResource API, including its resource metadata and read callback behavior. Clarify how registered resources should be listed and how execution by name or URI should return content, then define coverage for both lookup forms. Done means the server exposes the requested metadata and resource content behavior.