Add plugin telemetry bridge capability

Expose telemetry.track through the plugin SDK and server host bridge, forward plugin-prefixed events into the shared telemetry client, and demonstrate the capability in the kitchen sink example.\n\nCo-Authored-By: Paperclip <noreply@paperclip.ing>

packages/plugins/sdk/src/protocol.ts

@@ -519,6 +519,12 @@ export interface WorkerToHostMethods {
     result: void,
   ];
 
+  // Telemetry
+  "telemetry.track": [
+    params: { eventName: string; dimensions?: Record<string, string | number | boolean> },
+    result: void,
+  ];
+
   // Logger
   "log": [
     params: { level: "info" | "warn" | "error" | "debug"; message: string; meta?: Record<string, unknown> },