Investigate support for Resources and Prompts

[esnible]

The MVP is focused on tool calls.

The next version should also gateway Resources and Prompts.

[david-martin]

Spec docs:

• https://modelcontextprotocol.io/specification/2025-06-18/server/prompts
• https://modelcontextprotocol.io/specification/2025-06-18/server/resources

[esnible]

The server https://github.com/modelcontextprotocol/servers/tree/main/src/everything is said to offer "everything". It might be a good example to test if we gateway everything.