Description

This PR implements CEP-47 Server Redirect support for @contextvm/sdk, adding full end-to-end middleware and re-issuance capabilities. It faithfully follows the mentor's callback-driven middleware design without mutating the stateless initialization lifecycle, and allows the client to transparently handle complex chained redirects with a safety hop cap.

Features Included

1. Server-Side Redirect (withServerRedirect):
   • A middleware that accepts a resolveRedirect callback.
   • It is decoupled from state configuration (e.g., stateless mode). It evaluates the incoming JSON-RPC request and if a redirect is needed, emits the standard -32044 MCP error payload with the target pubkey and relays.
2. Client-Side Redirect (withClientRedirect):
   • Intercepts incoming messages looking for the -32044 error.
   • Transparently handles the redirect by spinning up a new NostrClientTransport to the target server.
   • Properly routes subsequent messages and replaces the old transport for a seamless caller experience.
   • Includes cycle/loop detection with a customizable maxRedirects option (defaulting to 5 hops).
3. Bug Fixes:
   • Fixed a bug in ApplesauceRelayPool message handling. applesauce-relay emits raw events rather than typed wrapper objects in the req() subscription. Fixed the message handler so that subscriptions correctly fire on events.
   • Fixed a double prepending issue in mock-relay-server connection mapping which caused test relay timeouts.
4. Integration & Proxy:
   • withClientRedirect is cleanly hooked up into NostrMCPProxy alongside payments.
   • Lint rules pass and TypeScript is fully typed.

Testing

• End-to-end single redirect (Client -> Server A -> Server B -> responds)
• Chained redirects (Client -> Server A -> Server B -> Server C -> responds)
• Infinite Loop detection (Client -> A -> B -> A -> Error thrown via McpError -32044)

All unit tests and E2E integration tests are passing successfully.

Changeset

Included a changeset for the upcoming release.