Create a standalone ad group

Ad sets (Google ad groups) synced for the connection, optionally filtered by platform and campaignId. Reads the `ad_sets` table directly, independent of the `ads` rollup GET /v1/ads/tree uses, so a newly created standalone ad group with no ad yet (POST /v1/ads/ad-sets, Google only) is visible here even though it is invisible in the tree until an ad joins it via `adSetId` on POST /v1/ads/create. Returns at most 500 rows, newest first. **Status freshness.** `status`, `configuredStatus`, `platformStatus`, `platformAdSetStatus` and `platformCampaignStatus` are the values Zernio last stored. Background sync refreshes them, typically within 15 to 60 minutes (Google up to about 3 hours), and ended or long-paused objects may be refreshed less often. Zernio's own status writes re-read the switches they change. A change made in the platform's own ads manager therefore shows up here only after the next sync. Controllers that act on a switch should pass `live=true`, which reads the switches from the platform now, stores them, and returns `statusReadAt` (null when the read failed and the stored values were returned). With `live=true` (which needs a `campaignId` or `adSetId` filter) each listed ad set's own switch (`platformAdSetStatus`) is read live, for the first 20 rows; later rows keep their synced value with `statusReadAt: null`. Live reads cover TikTok, Meta, Google and OpenAI. The rolled-up `status` is not re-derived by a live read. On TikTok the same live read also returns the ad group's applied `optimizationGoal` and `billingEvent`, as TikTok's adgroup/get reports them, so you can verify the goal TikTok applied rather than the one you requested. It also returns `nativeSettings`: TikTok's own adgroup/get record for the ad group, verbatim and read in that same call (budget, budget_mode, schedule, placements, locations, ages, gender, languages, interests, actions, audiences and exclusions), plus the advertiser's currency and timezone. TikTok's `schedule_start_time` / `schedule_end_time` are UTC wall clocks ("YYYY-MM-DD HH:MM:SS", no offset); Ads Manager displays them in `advertiser_timezone`. `configReadAt` says when it was read; it is null on every row whose native settings were not read now, so never treat a null as a match. These are read, not retained create payloads, and are not stored.