Delete every object under a key prefix (folder) in a bucket

Soft-deletes every object on the specified branch whose key starts with prefix, in a single call. Intended to back a "delete folder" action in an object browser: a prefix of app/avatars/ removes every object beneath that folder. Served by the user's session (no customer S3 credentials required).

prefix must be non-empty, end with /, be at most 1024 bytes, and contain no control characters - a partial-segment prefix cannot accidentally delete sibling keys. Returns the number of objects soft-deleted (deleted), which may be 0 when no live object matched the prefix on this branch.

Only objects physically present on this branch are tombstoned; objects inherited from an ancestor branch via copy-on-write (not materialized on this branch) are out of scope.

Note: This endpoint is currently in Private Beta.