fix(logging): disable console telemetry sink by default (#3623)

The current span processing dumps so much junk on the console that it
makes actual understanding of what is going on in the server impossible.
I am killing the console sink as a default. If you want, you are always
free to change your run.yaml to add it.

Before: 
<img width="1877" height="1107" alt="image"
src="https://github.com/user-attachments/assets/3a7ad261-e2ba-4d40-9820-fcc282c8df37"
/>

After:
<img width="1919" height="470" alt="image"
src="https://github.com/user-attachments/assets/bc7cf763-fba9-4e95-a4b5-f65f6d1c5332"
/>

llama_stack/distributions/starter-gpu/run.yaml

@@ -159,7 +159,7 @@ providers:
     provider_type: inline::meta-reference
     config:
       service_name: "${env.OTEL_SERVICE_NAME:=\u200B}"
-      sinks: ${env.TELEMETRY_SINKS:=console,sqlite}
+      sinks: ${env.TELEMETRY_SINKS:=sqlite}
       sqlite_db_path: ${env.SQLITE_STORE_DIR:=~/.llama/distributions/starter-gpu}/trace_store.db
       otel_exporter_otlp_endpoint: ${env.OTEL_EXPORTER_OTLP_ENDPOINT:=}
   post_training: