internal/rosa: lazy initialise all artifacts

This improves performance, though not as drastically as lazy initialising llvm.

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

internal/rosa/busybox.go

@@ -100,9 +100,7 @@ func newBusyboxBin() pkg.Artifact {
 	)
 }
 
-// NewBusybox returns a [pkg.Artifact] containing a dynamically linked busybox
-// installation usable within the [Toolchain] it is compiled against.
-func (t Toolchain) NewBusybox() pkg.Artifact {
+func (t Toolchain) newBusybox() pkg.Artifact {
 	const (
 		version  = "1.37.0"
 		checksum = "Ial94Tnt7esJ_YEeb0AxunVL6MGYFyOw7Rtu2o87CXCi1TLrc6rlznVsN1rZk7it"
@@ -114,8 +112,8 @@ func (t Toolchain) NewBusybox() pkg.Artifact {
 	}
 
 	return t.New("busybox-"+version, stage3Concat(t, []pkg.Artifact{},
-		t.NewMake(),
-		t.NewKernelHeaders(),
+		t.Load(Make),
+		t.Load(KernelHeaders),
 	), nil, slices.Concat([]string{
 		"ROSA_BUSYBOX_ENABLE=" + strings.Join([]string{
 			"STATIC",
@@ -354,3 +352,4 @@ index 64e752f4b..40f5ba7f7 100644
  		}`)),
 	))
 }
+func init() { artifactsF[Busybox] = Toolchain.newBusybox }