JWT verification adapter that delegates to boundary/user module.

Wraps wagoe.user.shell.auth/validate-jwt-token to provide IJWTVerifier
protocol implementation. Avoids direct dependency from core layer to user module.

Responsibilities (Shell/I/O):
- Call user module for JWT verification (I/O - external dependency)
- Transform user module response to expected format
- Handle verification errors

Redis-backed IPubSubManager: topic subscriptions in Redis sets so they are
visible cluster-wide.

Keys (optionally prefixed):
  topic:{t}  -> SET of connection-id strings
  conn:{id}  -> SET of topic strings   (reverse index)

subscribe / unsubscribe apply both SADD/SREM atomically in a MULTI/EXEC.
No explicit DEL on topic sets: Redis auto-removes a set key when its last
member is removed, so empty topics disappear and the check-then-act DEL race
cannot occur.

WebSocket connection adapter for Ring/Jetty.

Wraps Ring WebSocket implementation to provide IWebSocketConnection protocol.
Handles JSON encoding/decoding and WebSocket frame transmission.

Responsibilities (Shell/I/O):
- Send messages over WebSocket (I/O operation)
- Close WebSocket connections (I/O operation)
- JSON encoding (external format transformation)
- Error handling and logging