Function content_hash_name 

pub fn content_hash_name(bytes: &[u8], ext: &str) -> String

Content-addressed identity <sha256> / <sha256>.<ext> derived from raw bytes (the full hex SHA-256 digest). Shared by blob materialization and outbound delivery URIs so both use the same opaque, URI-safe, collision-resistant name — the identity is the full 256-bit digest and depends on content, never on a caller-supplied filename, so distinct content never aliases one name and reserved characters can’t leak.