Stop and delete a campaign

Stops the campaign and deletes it. This is a soft delete: sending halts immediately, open task mirrors are cleared, and the campaign disappears from GET /business/campaigns and from GET /business/campaigns/{campaignId}. Contacts keep their per-contact state, and sends already delivered are unaffected. Deleting a campaign that is already deleted answers 404, like every other endpoint here: once deleted, a campaign does not exist on this surface. Only the token owner's own campaigns can be deleted. Rate limit: this endpoint and POST /business/campaigns/{campaignId}/stop share a tighter cap of 10 requests/minute and 100/day, applied inside the shared campaigns bucket of 30 requests/minute and 1,000/day per token owner (shared by every campaign, scheduled-send, campaign-template and knowledge-hub endpoint).

Errors:

• 404 CAMPAIGN_NOT_FOUND — No campaign with this id exists, it belongs to another account (including a campaign delegated to you or shared by your team's visibility settings), or it has been deleted.
• 409 CAMPAIGN_BUSY — Another approve or stop is holding this campaign's activation lock. Retry in a few seconds.
• 422 VALIDATION_FAILED — campaignId is not a 24-character hex id.
• 429 RATE_LIMITED — Either this endpoint's own cap (10 requests/minute, 100/day) or the shared campaigns bucket (30/minute, 1,000/day for this token owner, shared by every /business/campaigns, /business/scheduled-sends, /business/campaign-templates and /business/knowledge-hubs call) was exceeded. The RateLimit-* headers on the response describe the shared bucket, so a refusal from this endpoint's own cap can still report requests remaining and carries no Retry-After.
• 500 UNEXPECTED_ERROR — An unhandled failure; the detail stays in our logs and is never returned.

Requires one of the following token scopes: campaigns.