Problem:
An unreplayable Visual operation does not emit a CmdAtom event. That's
maybe not super important, but it hints at a flaw in how `vatom`
"voiding" is plumbed: `vatom.state=kVatomVoid` replaces the "kind", so
that info is lost to later parts in the lifecycle.
Solution:
- Define `VatomState` as "flags", so `kVatomVoid` can "poison"
`vatom.state` without losing its kind flag.
- Unify `lhs`: always report the original user input in `CmdAtom.lhs`,
for all kinds of user actions: visual, "translated"/"stuffed" cmds,
and dot-repeat (".") itself.
- Unreplayable Visual atom emits CmdAtom with non-empty `lhs` and empty
`keys`, like a mapping/macro composite.
31de0d69fc
