Ad rate per prompt

Ad rate for each prompt that ran in the window, how many distinct advertisers contested it, and the advertiser that rendered the most ad cards on it. This is the single call behind "unique advertisers per prompt" — one advertiser counts once per prompt, so the column sums above the domain-wide count on the overview. Prompts that drew no ads are included with a zero rate, zero advertisers and no top advertiser. Ordered by absolute ad volume, NOT by ad rate — a rate ranking would put a prompt that ran twice and drew one ad above one that ran 400 times and drew 120. `total` reports how many prompts ran in the window, so a truncated list is distinguishable from the whole set; page past the cap with `page`/`limit`. Each row also carries the analysed brand's own ads on that prompt, so a prompt that draws ads but never yours is visible as a gap rather than as silence, and the ads assignment status set on the prompt itself. That status is customer-owned and reported verbatim: it is never inferred from the ad counts on the row.