The implementations of the dropDatabase and dropCollection commands currently reside in the storage_engine_integration module, while their declarations (IDL files) are in the shard_role module. The createIndexes command implementation instead resides in the index_builds module.

The goal of this ticket is to move these implementations into the shard_role/ddl directory (and therefore temporarily into the shard_role module). In a subsequent change, not covered by this ticket, the shard_role/ddl directory will be integrated into the global_catalog module.