image: introduce image kinds for Fedora

Implement all of Fedora in terms of this new abstraction. What used to be the
manifest functions (and before that the pipeline functions) are now the image
functions, whose purpose is to instantiate the right image kind structs from the
image type definitions we currently have in the distro definition.

internal/image/container.go

@@ -0,0 +1,47 @@
+package image
+
+import (
+	"math/rand"
+
+	"github.com/osbuild/osbuild-composer/internal/artifact"
+	"github.com/osbuild/osbuild-composer/internal/environment"
+	"github.com/osbuild/osbuild-composer/internal/manifest"
+	"github.com/osbuild/osbuild-composer/internal/platform"
+	"github.com/osbuild/osbuild-composer/internal/rpmmd"
+	"github.com/osbuild/osbuild-composer/internal/runner"
+	"github.com/osbuild/osbuild-composer/internal/workload"
+)
+
+type BaseContainer struct {
+	Base
+	Platform         platform.Platform
+	OSCustomizations manifest.OSCustomizations
+	Environment      environment.Environment
+	Workload         workload.Workload
+	Filename         string
+}
+
+func NewBaseContainer() *BaseContainer {
+	return &BaseContainer{
+		Base: NewBase("base-container"),
+	}
+}
+
+func (img *BaseContainer) InstantiateManifest(m *manifest.Manifest,
+	repos []rpmmd.RepoConfig,
+	runner runner.Runner,
+	rng *rand.Rand) (*artifact.Artifact, error) {
+	buildPipeline := manifest.NewBuild(m, runner, repos)
+	buildPipeline.Checkpoint()
+
+	osPipeline := manifest.NewOS(m, buildPipeline, img.Platform, repos)
+	osPipeline.OSCustomizations = img.OSCustomizations
+	osPipeline.Environment = img.Environment
+	osPipeline.Workload = img.Workload
+
+	ociPipeline := manifest.NewOCIContainer(m, buildPipeline, osPipeline)
+	ociPipeline.Filename = img.Filename
+	artifact := ociPipeline.Export()
+
+	return artifact, nil
+}