Resolve Ad Accounts

Resolve the ad-account id for each target. Used by the agent plan destinations popover to build bulk Ads Manager deep-links — those need ?act=<account> to land on the right account.

Single ClickHouse pass: campaign/ad-set/ad ids are namespace-unique within a workspace, so we don't need to filter by level or channel at the SQL layer — we just OR the three IN clauses and read which id column matched on each row. The row carries channel, so multi-channel requests disambiguate naturally on the way back.