What: Added telemetry for A/B test experiment exposure tracking.
Details:
- Tracks which users are exposed to which experiment variations
- Events include: experiment ID, variation ID, device ID, user attributes
- Batched transmission via OpenTelemetry log pipeline
- Internal analytics only - no user-visible impact
- Evidence:
rNB()at line 231011,tNB()at line 231925,aNB()at line 230979