Summary

There are a number of duplicate, misleading, and inconsistent types across the DE backend. This issue will outline some potential problems and solutions as we work toward a more consistent type framework.

Work Items

• SignalHit - Uses ES hit terminology, but is not actually a hit (it's used to build alerts in build_bulk_body.ts)... there is also a different type named SignalHit in the cases plugin => Remove in favor of AlertBody below.
• SignalSource - TODO
• SignalSourceHit - Like above, uses hit terminology, but is used to construct alerts.
• WrappedSignalHit - Same as above.
• RACAlert - This is the new type to replace SignalHit, but should be renamed to AlertBody.
• WrappedRACAlert - Rename to WrappedAlertBody.
• SimpleHit - Fairly useless type... just BaseHit parameterized with an optional @timestamp.
• Signal - Will be deprecated.
• SignalRuleAlertTypeDefinition - Remove. (Need to wait for rule preview work)
• Threshold types - move to different location.