fix(desktop): retain new-workspace image attachments across navigation

apps/desktop/src/renderer/routes/_authenticated/_dashboard/new-workspace/page.tsx

@@ -2,6 +2,7 @@ import { PromptInputProvider } from "@superset/ui/ai-elements/prompt-input";
 import { createFileRoute } from "@tanstack/react-router";
 import { NewWorkspaceScreen } from "renderer/routes/_authenticated/components/DashboardNewWorkspaceModal/components/NewWorkspaceScreen";
 import { DashboardNewWorkspaceDraftProvider } from "renderer/routes/_authenticated/components/DashboardNewWorkspaceModal/DashboardNewWorkspaceDraftContext";
+import { newWorkspaceAttachmentsStore } from "renderer/stores/new-workspace-attachments";
 
 export const Route = createFileRoute(
 	"/_authenticated/_dashboard/new-workspace/",
@@ -23,7 +24,7 @@ function NewWorkspacePage() {
 	const { projectId } = Route.useSearch();
 	return (
 		<DashboardNewWorkspaceDraftProvider onClose={() => {}}>
-			<PromptInputProvider>
+			<PromptInputProvider attachmentsStore={newWorkspaceAttachmentsStore}>
 				<NewWorkspaceScreen isOpen preSelectedProjectId={projectId ?? null} />
 				{/* Window-drag surface replacing the hidden TopBar's drag region.
 				    Stops short of the top-right corner so the screen's naming

apps/desktop/src/renderer/routes/_authenticated/_dashboard/v2-workspaces/components/NewWorkspaceEmptyScreen/NewWorkspaceEmptyScreen.tsx

@@ -1,6 +1,7 @@
 import { PromptInputProvider } from "@superset/ui/ai-elements/prompt-input";
 import { NewWorkspaceScreen } from "renderer/routes/_authenticated/components/DashboardNewWorkspaceModal/components/NewWorkspaceScreen";
 import { DashboardNewWorkspaceDraftProvider } from "renderer/routes/_authenticated/components/DashboardNewWorkspaceModal/DashboardNewWorkspaceDraftContext";
+import { newWorkspaceAttachmentsStore } from "renderer/stores/new-workspace-attachments";
 
 /**
  * Experiment test arm (new-workspace-screen): replaces the "No workspaces yet"
@@ -12,7 +13,7 @@ import { DashboardNewWorkspaceDraftProvider } from "renderer/routes/_authenticat
 export function NewWorkspaceEmptyScreen() {
 	return (
 		<DashboardNewWorkspaceDraftProvider onClose={() => {}}>
-			<PromptInputProvider>
+			<PromptInputProvider attachmentsStore={newWorkspaceAttachmentsStore}>
 				<NewWorkspaceScreen isOpen preSelectedProjectId={null} />
 			</PromptInputProvider>
 		</DashboardNewWorkspaceDraftProvider>

apps/desktop/src/renderer/routes/_authenticated/components/DashboardNewWorkspaceModal/DashboardNewWorkspaceModal.tsx

@@ -11,6 +11,7 @@ import {
 } from "@superset/ui/dialog";
 import { useNavigate } from "@tanstack/react-router";
 import { useEffect, useRef } from "react";
+import { newWorkspaceAttachmentsStore } from "renderer/stores/new-workspace-attachments";
 import {
 	useCloseNewWorkspaceModal,
 	useNewWorkspaceModalOpen,
@@ -66,7 +67,7 @@ export function DashboardNewWorkspaceModal() {
 
 	return (
 		<DashboardNewWorkspaceDraftProvider onClose={closeModal}>
-			<PromptInputProvider>
+			<PromptInputProvider attachmentsStore={newWorkspaceAttachmentsStore}>
 				<PromptInputResetSync />
 				<Dialog
 					modal

apps/desktop/src/renderer/routes/_authenticated/components/DashboardNewWorkspaceModal/components/NewWorkspaceScreen/NewWorkspaceScreen.tsx

@@ -44,6 +44,7 @@ import { electronTrpc } from "renderer/lib/electron-trpc";
 import { showHostServiceUnavailableToast } from "renderer/lib/host-service-unavailable";
 import { SupersetIcon } from "renderer/routes/_authenticated/onboarding/providers/components/SupersetIcon";
 import { useLocalHostService } from "renderer/routes/_authenticated/providers/LocalHostServiceProvider";
+import { newWorkspaceAttachmentPaths } from "renderer/stores/new-workspace-attachments";
 import { useNewWorkspacePromptContext } from "renderer/stores/new-workspace-prompt-context";
 import { useV2WorkspaceCreateDefaultsStore } from "renderer/stores/v2-workspace-create-defaults";
 import { useDashboardNewWorkspaceDraft } from "../../DashboardNewWorkspaceDraftContext";
@@ -118,9 +119,6 @@ export function NewWorkspaceScreen({
 	// case (Esc-cancelled drags, drops outside the window) that an enter/leave
 	// counter gets permanently stuck on.
 	const [isDraggingFiles, setIsDraggingFiles] = useState(false);
-	// Source paths for dropped/picked files, keyed by filename — the attachment
-	// items only keep an object URL, and Finder reveal needs the original path.
-	const attachmentPathsRef = useRef(new Map<string, string>());
 	useEffect(() => {
 		if (!isOpen) return;
 		let timer: number | null = null;
@@ -132,8 +130,8 @@ export function NewWorkspaceScreen({
 					// Attachment items only expose the basename, so the map is
 					// name-keyed; a second same-named file from elsewhere makes the
 					// name ambiguous — poison it so no card reveals the wrong file.
-					const existing = attachmentPathsRef.current.get(file.name);
-					attachmentPathsRef.current.set(
+					const existing = newWorkspaceAttachmentPaths.get(file.name);
+					newWorkspaceAttachmentPaths.set(
 						file.name,
 						existing !== undefined && existing !== path ? "" : path,
 					);
@@ -601,7 +599,7 @@ export function NewWorkspaceScreen({
 							))}
 							{visibleFiles.map((file) => {
 								const sourcePath = file.filename
-									? attachmentPathsRef.current.get(file.filename) || null
+									? newWorkspaceAttachmentPaths.get(file.filename) || null
 									: null;
 								return (
 									<AttachmentCard

apps/desktop/src/renderer/stores/new-workspace-attachments.test.ts

@@ -0,0 +1,64 @@
+import { beforeEach, describe, expect, it } from "bun:test";
+import {
+	newWorkspaceAttachmentPaths,
+	newWorkspaceAttachmentsStore,
+} from "./new-workspace-attachments";
+import { useNewWorkspaceDraftStore } from "./new-workspace-draft";
+
+const imageFile = {
+	id: "file-1",
+	type: "file" as const,
+	url: "blob:renderer/one",
+	mediaType: "image/png",
+	filename: "one.png",
+};
+
+describe("newWorkspaceAttachmentsStore", () => {
+	beforeEach(() => {
+		newWorkspaceAttachmentsStore.set([]);
+		newWorkspaceAttachmentPaths.clear();
+	});
+
+	it("retains files independent of any mounted provider", () => {
+		newWorkspaceAttachmentsStore.set([imageFile]);
+		expect(newWorkspaceAttachmentsStore.get()).toEqual([imageFile]);
+	});
+
+	it("keeps files across non-reset draft updates", () => {
+		newWorkspaceAttachmentsStore.set([imageFile]);
+		useNewWorkspaceDraftStore.getState().updateDraft({ prompt: "hello" });
+		expect(newWorkspaceAttachmentsStore.get()).toEqual([imageFile]);
+	});
+
+	it("clears files, revokes blob URLs, and drops source paths on draft reset", () => {
+		const revoked: string[] = [];
+		const original = URL.revokeObjectURL;
+		URL.revokeObjectURL = (url: string) => {
+			revoked.push(url);
+		};
+		try {
+			newWorkspaceAttachmentsStore.set([imageFile]);
+			newWorkspaceAttachmentPaths.set("one.png", "/tmp/one.png");
+
+			useNewWorkspaceDraftStore.getState().resetDraft();
+
+			expect(newWorkspaceAttachmentsStore.get()).toEqual([]);
+			expect(revoked).toEqual(["blob:renderer/one"]);
+			expect(newWorkspaceAttachmentPaths.size).toBe(0);
+		} finally {
+			URL.revokeObjectURL = original;
+		}
+	});
+
+	it("notifies subscribers when files change", () => {
+		let calls = 0;
+		const unsubscribe = newWorkspaceAttachmentsStore.subscribe(() => {
+			calls += 1;
+		});
+		newWorkspaceAttachmentsStore.set([imageFile]);
+		expect(calls).toBe(1);
+		unsubscribe();
+		newWorkspaceAttachmentsStore.set([]);
+		expect(calls).toBe(1);
+	});
+});

apps/desktop/src/renderer/stores/new-workspace-attachments.ts

@@ -0,0 +1,26 @@
+import { createPromptInputAttachmentsStore } from "@superset/ui/ai-elements/prompt-input";
+import { useNewWorkspaceDraftStore } from "renderer/stores/new-workspace-draft";
+
+/**
+ * Module-scoped attachment state for the new-workspace draft. Keeps attached
+ * files alive across navigation the same way the prompt text survives in
+ * useNewWorkspaceDraftStore — the create surfaces mount and unmount, this
+ * store does not.
+ */
+export const newWorkspaceAttachmentsStore = createPromptInputAttachmentsStore();
+
+/**
+ * Source paths for dropped/picked files, keyed by filename — attachment items
+ * only keep an object URL, and Finder reveal needs the original path. Module
+ * scoped so reveal keeps working for attachments restored after navigation.
+ */
+export const newWorkspaceAttachmentPaths = new Map<string, string>();
+
+// A draft reset (successful create or explicit discard) clears attachments
+// with it, even while no create surface is mounted.
+useNewWorkspaceDraftStore.subscribe((state, prevState) => {
+	if (state.resetKey !== prevState.resetKey) {
+		newWorkspaceAttachmentsStore.clear();
+		newWorkspaceAttachmentPaths.clear();
+	}
+});