Thanks Gavin Wahl for the report, and Tim Graham for the review.

The test now also checks whether the sent message's attachment has the expected
name, content and mime type.

Fixed #27026 -- Fixed state initialization of bulk_create() objects if can_return_ids_from_bulk_insert.

* Added the index name to its deconstruction.
* Added indexes to sqlite3.schema._remake_table() so that indexes
  aren't dropped when _remake_table() is called.

Thanks timgraham & MarkusH for review and advice.

The underlying hasher only generates strings containing ASCII
characters so this is merely a cosmetic change.

Thanks weidwonder for the report.

This removes the dependency of the Index class on its 'model'
attribute.

Thanks marktranchant for the report and review.

Thanks mcgeeco for reporting, and claudep and timgraham for review.