feat: show last run logs/result when a script node is selected

frontend/src/lib/components/ScriptEditor.svelte

@@ -1250,8 +1250,37 @@
 		}
 		aiChatManager.saveAndClear()
 		aiChatManager.changeMode(AIMode.SCRIPT)
+		if (customUi?.previewPanel?.loadLastRunOnMount) {
+			void loadLastRunIntoTestPanel()
+		}
 	})
 
+	// Pull the most recent top-level completed job for this script path and
+	// feed it through the JobLoader so the preview pane renders its logs +
+	// result. Best-effort: any error (no job yet, network blip) leaves the
+	// panel empty rather than surfacing a toast — this is a passive "show
+	// what's there" affordance, not a user action. Skipped when a test is
+	// already running so a live job's stream is never clobbered.
+	async function loadLastRunIntoTestPanel(): Promise<void> {
+		if (!path || !$workspaceStore) return
+		if (testIsLoading || testJob !== undefined) return
+		try {
+			const jobs = await JobService.listCompletedJobs({
+				workspace: $workspaceStore,
+				scriptPathExact: path,
+				hasNullParent: true,
+				perPage: 1,
+				orderDesc: true
+			})
+			const lastId = jobs[0]?.id
+			if (lastId && !testIsLoading && testJob === undefined) {
+				await jobLoader?.watchJob(lastId)
+			}
+		} catch (e) {
+			// Silent: empty preview pane is the natural fallback.
+		}
+	}
+
 	setLicense()
 	export async function setCollaborationMode() {
 		await setLicense()

frontend/src/lib/components/assets/AssetGraph/AssetGraphDetailsPane.svelte

@@ -812,7 +812,12 @@
 							hideArgs: true,
 							argsAboveLogs: true,
 							logsResultSideBySide: true,
-							downstreamSubscribers
+							downstreamSubscribers,
+							// Selecting a script node should immediately show
+							// "what happened last time it ran" — pulling the
+							// latest top-level completed job into the preview
+							// pane is far more useful than an empty placeholder.
+							loadLastRunOnMount: true
 						}
 					}}
 					bind:code={script.content}

frontend/src/lib/components/custom_ui.ts

@@ -84,6 +84,13 @@ export type PreviewPanelUi = {
 	// partitioned pipeline script that needs a `partition` arg to run).
 	// No-op when the script has no input properties.
 	argsAboveLogs?: boolean
+	// On mount, query the most recent top-level completed job for this
+	// script's path and load it into the preview pane so users immediately
+	// see the last run's logs/result instead of an empty panel. Used by the
+	// asset-graph details pane where selecting a script node should expose
+	// "what happened the last time this ran". No-op when a test is already
+	// in progress (we don't clobber a live run).
+	loadLastRunOnMount?: boolean
 }
 
 export type EditorBarUi = {