internal/rosa: create metadata alongside artifact

This enables deferring evaluation of azalea-based packages and fixes the longstanding quirk of version being disjoint from other metadata.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/pkg-config.go

@@ -24,9 +24,7 @@ func (t Toolchain) newPkgConfig() (pkg.Artifact, string) {
 	), version
 }
 func init() {
-	native.MustRegister(&Artifact{
-		f: Toolchain.newPkgConfig,
-
+	native.mustRegister(Toolchain.newPkgConfig, &Metadata{
 		Name:        "pkg-config",
 		Description: "a helper tool used when compiling applications and libraries",
 		Website:     "https://pkgconfig.freedesktop.org/",