feat: ability to cancel a draft

[madbob]

Second try in handling direct draft discarding.

Warning: here I've inverted the order of trash icon / draft status text at the bottom of the modal. In this setup the trash icon is always visible but the draft status is not, leaving the previous layout would move the discard button around the window in inconvenient way.

Superseeds #13175
Fixes #2492

[github-actions]

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