envision: query requested rather than installed packages

Signed-off-by: Shiloh Fen <[e-mail]>

src/atomic-xr/envision.nu

···
     packages: list<string>
 ] {
     let missing_packages = $packages
-    | each {|package|
-        if (rpm -q $package | complete | get exit_code) != 0 {
-            $package
-        }
-    }
+    | where $it not-in (rpm-ostree status --json | from json | get deployments | first | get requested-packages)
 
     if ($missing_packages | is-not-empty) {
         rpm-ostree install ...$missing_packages