fix: minor improvements (#676)

Author: Cahllagerfeld

src/components/dag-visualizer/add-manual-artifacts.ts

@@ -15,6 +15,11 @@ export function addManuallyAddedArtifacts(
 	missingNodes.forEach((missingNode) => {
 		const [stepName, artifactName] = missingNode.id.split("--");
 		const step = steps[stepName];
+
+		if (!step) {
+			return;
+		}
+
 		const existingNode = findExistingArtifactNode(nodes, missingNode);
 		const inputs = step.body?.inputs as { [key: string]: ArtifactVersion };
 		const outputs = step.body?.outputs as { [key: string]: ArtifactVersion };

src/components/dag-visualizer/extract-layout.ts

@@ -72,21 +72,19 @@ export function extractPlaceholderLayout(stepConfig: Record<string, StepOutput>)
 		});
 
 		// model artifacts or metadata
-		const modelArtifacts = step.config.model_artifacts_or_metadata as Record<
-			string,
-			ModelVersionLazyLoader
-		>;
+		const modelArtifacts =
+			(step.config.model_artifacts_or_metadata as Record<string, ModelVersionLazyLoader>) || {};
+
 		Object.keys(modelArtifacts).forEach((inputName) => {
 			const modelArtifactId = `${stepName}--${inputName}`;
 			addNode(modelArtifactId, "previewArtifact", inputName);
 			addEdge(modelArtifactId, stepName);
 		});
 
 		// client lazy loaded artifacts
-		const clientLazyLoadedArtifacts = step.config.client_lazy_loaders as Record<
-			string,
-			ClientLazyLoader
-		>;
+		const clientLazyLoadedArtifacts =
+			(step.config.client_lazy_loaders as Record<string, ClientLazyLoader>) || {};
+
 		Object.keys(clientLazyLoadedArtifacts).forEach((inputName) => {
 			const clientLazyLoadedArtifactId = `${stepName}--${inputName}`;
 			addNode(clientLazyLoadedArtifactId, "previewArtifact", inputName);