Delete a bucket

Deletes the bucket bucketId from the active scope. The UI exposes this from the bucket detail header ("Delete"), the list row menu ("Delete bucket") and as a bulk action over selected rows. Deletion enters a visible asynchronous workflow (soft delete): the bucket stops accepting new writes, its objects and versions are drained, and the resource then disappears from scoped listings. A failed deletion leaves the bucket in a recoverable, queryable state. Validation: bucketId must reference an existing, non-deleted bucket in the scope (unknown → 404 NOT_FOUND); deletion must not be blocked by an unresolved dependency such as remaining objects when force-emptying is not permitted, or access-log delivery from another bucket (blocked → 409 DEPENDENCY_BLOCKED); a legacy delete-protected bucket (objectLock: true) that still holds objects cannot be deleted through this API (→ 409 LOCKED); a bucket already deleting cannot be deleted again (→ 409 CONFLICT, no second Operation); caller must hold a destructive-action role (owner|admin|contributor), otherwise 403 FORBIDDEN. Async & state: Asynchronous — returns 202 with an Operation. The bucket transitions active → deleting → deleted (soft delete; subsequent reads return 404 while activity retains the audit trail). Progress is emitted as resource.updated SSE frames (kind storage.bucket, patch {status, objectCount, sizeBytes}) followed by a terminal operation.completed frame. Errors: 401 unauthenticated; 403 caller lacks destructive permission; 404 unknown scopeId/bucketId; 409 DEPENDENCY_BLOCKED objects or log-delivery dependants block removal; 409 LOCKED legacy delete protection, the bucket still holds objects; 409 CONFLICT the bucket is already being deleted; 412 If-Match ETag does not match the current bucket revision; 500 unexpected backend failure. Idempotency/Concurrency: Idempotency-Key is optional; replaying the same key returns the original 202 Operation without enqueuing a second deletion. If-Match with the ETag from the detail read protects against deleting a concurrently modified bucket.