docs(telemetry): update Console Gateway backend attribution

[XXPermanentXX]

Summary

• document that Console Gateway user data is distinguished directly by the backend
• clarify that this attribution does not depend on x-dashscope-source-config
• keep AEM authMethod=console documented as separate command-side telemetry

Verification

• vp check — passed with 0 errors and 3 existing warnings
• git diff --check — passed
• vp test on the unchanged origin/main baseline — 1459 passed, 25 failed, 51 skipped; failures are in existing local agent-detection assertions, live model/memory calls, and unrelated dataset/media expectations