List items are space-separated tokens

A list variable is typed string[], number[] or boolean[]. At the prompt and in a script, its value is the items separated by spaces, each quoted like a command argument: tags "two words" b. A lone "" is the empty list, and an empty item next to others is an error. The console prints a list the same way, so a printed value reads back as the same items. Revert, script saves and mirrored writes all go through that text.

Considered Options

• A comma separator. redo "Mod+y, Mod+Shift+z" needs quotes around the whole list, and an item holding a comma needs an escape the prompt does not have.
• A JSON array. ["Mod+y","Mod+Shift+z"] is unambiguous but quotes every string, which the prompt never asks for elsewhere.
• A list flag on each scalar type. Every switch over type would need a second check, and set could not be typed from one discriminant.
• type: "list" with an items field. It types set, but every dispatch over type still needs a nested one over items.

Consequences

• A list cannot hold an empty string. A getter that returns one makes the variable unreadable, so [""] never prints as the empty list.
• Command arguments stay scalar; a rest string argument already takes the rest of the line.
• A separator option on the variable is possible later without changing the default.