Get Stats Extended Overview

Conversion-side aggregate counts for the current user. Split from StatsOverviewResponse because these branches scan substantially more rows for high-volume users (notably the contacts and follows branches).

• dms_sent: DMs successfully sent — event_tracker.AUTODM_DM_SENT for normal automations plus flow_execution_step rows whose node_type is one of the four message-sending node types (PLAIN_TEXT_MESSAGE, BUTTON_TEXT_MESSAGE, BUTTON_TEXT_IMAGE_MESSAGE, CAROUSEL_BUTTON_TEXT_IMAGE_MESSAGE) and whose status is COMPLETED.
• follows: distinct users who received a follow request from a normal automation and were subsequently sent a DM — same logic as event_tracker.get_new_followers_summary but user-wide rather than per-automation.
• contacts: count of contact rows for the user. For range=all this is the lifetime audience size; for any other range it's contacts first seen within the window (i.e. contacts gained).

CTR is derived on the frontend as clicks / dms_sent, so CTR only renders once both this endpoint and /v1/stats/overview resolve.