Title: Pinterest: daily account-level impressions and engagement

Please add account-level daily impressions and engagements for Pinterest (Pinterest's user_account/analytics, IMPRESSION and ENGAGEMENT), alongside the follower history already in /v1/accounts/follower-stats.

Why: pin-level analytics cannot stand in for the account figure, because pins keep surfacing for months. One of our accounts has published no pins since April 2026 and still receives 4,000–7,000 impressions a month. Pin analytics are tracked only from connection, so none of that is visible. The account figure is the only one that captures it, and it is the only reason we keep a second supplier for Pinterest.