Landrace between #439 (installability tests fixture) and #451 (added
`path: Option<String>` to `TarballResolution`). Both merged green
against their own bases but main's tip won't compile:
error[E0063]: missing field `path` in initializer of `TarballResolution`
--> crates/package-manager/src/installability/tests.rs:56:49
Add the missing field with `path: None` so the struct literal matches
the current `TarballResolution` shape.