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# Description
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Small refactor I noticed while writing a test with engine events. We
always had to call `NewEvent` with the tag and payload value for an
event and these _had_ to match up else the engine panics. But we can
just pass the payload and type switch to work out the tag. Means one
less parameter to pass to `NewEvent` and pretty much no chance of it
going wrong. To ensure there's really no chance I've added a generic
union type so you can only pass payload types to this method now.
Cancel had to be handled separately because it doesn't have a payload
type, it's just nil.
This PR implements the new policy transforms feature, which allows
policy packs to not only issue warnings and errors in response to policy
violations, but actually fix them by rewriting resource property state.
This can be used, for instance, to auto-tag resources, remove Internet
access on the fly, or apply encryption to storage, among other use
cases.
highlighting. The service doesn't currently support ANSI control
codes so all ANSI control codes are removed before being sent to
the service, but still displayed in the CLI.