dashes are wrongly considered as token boundaries (specifically, in Goto Definition)

given the following code

def foo-bar [] { }

def baz [] {
    foo-bar
}

in the foo-bar call inside baz,

1. Goto Definition on the foo links to the token foo in def foo-bar
2. Goto Definition on the bar links to the token bar in def foo-bar
3. No Goto Definition on the dash between foo and bar
4. Hovering on any part of foo-bar including the dash, correctly shows the information for foo-bar

instead, for 1-3, all parts of the identifier should link to the token foo-bar of def foo-bar

(note that nushell recommends kebab-case for function names, so this is a common thing.)

Reproduce the issue in VS Code using the supplied Nushell snippet, then inspect the extension's Goto Definition implementation and its identifier-boundary handling. Done means selecting foo, the dash, or bar in foo-bar all links to the foo-bar definition, while the existing hover behavior remains correct.