Delete Namespace

This endpoint deletes a namespace and ALL its resources including: - All buckets (with S3 objects, batches, uploads) - All collections (with Qdrant points, cache, webhooks) - All clusters (with Ray jobs, executions, triggers, S3 artifacts) - All retrievers (with executions, evaluations, interactions, cache) - Remaining MongoDB collections (tasks, uploads, taxonomies, API keys, etc.) - All S3 objects with namespace prefix - Qdrant collection (namespace's vector database) - All namespace cache (across all scopes) - Analytics data (ClickHouse tables) - Namespace metadata

The deletion is performed asynchronously. Returns a task_id that can be used
to poll for deletion progress via GET /v1/tasks/{task_id}.

⚠️  WARNING: This operation is irreversible and will delete ALL data in the namespace!