Support multiple keywords in a single message

[genebean]

If multiple key words such as rescan and latest are present, each should be acted up in order. Ideally it would do the actions in the order listed serially so that action two reflects the work/results of action one.

Sample use case flow

1. Post this message: “Please rescan @[email protected] and show me the latest episode”
2. A rescan of 5704574 happens
3. A reply is posted stating the rescan is complete
4. A reply to the previous reply is posted showing the latest episode

Use case for above flow

Someone looks at a podcast on the index, or at its actor in Mastodon that they already follow, and notices its most recent episode isn’t showing. They could send this singe message and have the rescan done and see if it fixed the problem.

[genebean]

Originally discussed at https://fosstodon.org/@genebean/111841885051810395