Find TikTok spend with nothing to show for it

Lists the ad groups and ads that spent real money over a window and produced no conversions, excluding anything still in its learning period or too thin to judge. Use when: the user asks what to cut, where budget is leaking, or why the account's CPA is high. Run it before recommending any pause. Do not pause anything from this list without showing it to the user first, and do not use it on a window shorter than a week — TikTok needs roughly 7 days per ad group before its numbers mean anything, and this tool excludes newer ones for exactly that reason. Do not treat "no conversions" as proof of failure when the account has no working pixel: if every ad group shows zero, the problem is measurement, not delivery. Check tiktok_list_pixels before drawing any conclusion. Returns each candidate with its spend, impressions, clicks and how long it has been running, plus the total that could be reclaimed. Anything under 1000 impressions is listed separately as "too thin to judge" rather than recommended — a cheap ad group that has barely run has not failed yet. If the user wants to act, tiktok_pause_ad_group and tiktok_pause_ad do it one object at a time, each with its own confirmation.