chore: Update rmcp sdk to 0.8.x

Author: swcollard

Cargo.lock

@@ -50,7 +50,7 @@ regex = "1.11.1"
 reqwest-middleware = "0.4.2"
 reqwest-tracing = { version = "0.5.8", features = ["opentelemetry_0_30"] }
 reqwest.workspace = true
-rmcp = { version = "0.6", features = [
+rmcp = { version = "0.8", features = [
   "server",
   "transport-io",
   "transport-sse-server",