feat(api): add chartRef to CozystackResourceDefinition

Replace the chart field with chartRef for referencing Helm charts via
ExternalArtifact resources. This enables the Package controller to
manage chart sources centrally.

Changes:
- Add chartRef field to CozystackResourceDefinition spec
- Remove chart field (deprecated)
- Remove validation (moved to controller)
- Update lineage mapper for new field structure
- Regenerate openapi specs

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: Andrei Kvapil <kvapss@gmail.com>

pkg/cmd/server/start.go

@@ -169,13 +169,10 @@ func (o *CozyServerOptions) Complete() error {
 			Release: config.ReleaseConfig{
 				Prefix: crd.Spec.Release.Prefix,
 				Labels: crd.Spec.Release.Labels,
-				Chart: config.ChartConfig{
-					Name: crd.Spec.Release.Chart.Name,
-					SourceRef: config.SourceRefConfig{
-						Kind:      crd.Spec.Release.Chart.SourceRef.Kind,
-						Name:      crd.Spec.Release.Chart.SourceRef.Name,
-						Namespace: crd.Spec.Release.Chart.SourceRef.Namespace,
-					},
+				ChartRef: config.ChartRefConfig{
+					Kind:      crd.Spec.Release.ChartRef.Kind,
+					Name:      crd.Spec.Release.ChartRef.Name,
+					Namespace: crd.Spec.Release.ChartRef.Namespace,
 				},
 			},
 		}