Emdash source with visual editor image upload fix

Fixes:
1. media.ts: wrap placeholder generation in try-catch
2. toolbar.ts: check r.ok, display error message in popover

packages/admin/tests/components/SaveButton.test.tsx

@@ -0,0 +1,45 @@
+import * as React from "react";
+import { describe, it, expect } from "vitest";
+
+import { SaveButton } from "../../src/components/SaveButton";
+import { render } from "../utils/render.tsx";
+
+describe("SaveButton", () => {
+	it("shows 'Save' when dirty and not saving", async () => {
+		const screen = await render(<SaveButton isDirty={true} isSaving={false} />);
+		await expect.element(screen.getByText("Save")).toBeInTheDocument();
+		await expect.element(screen.getByRole("button")).toBeEnabled();
+	});
+
+	it("shows 'Saving...' when saving", async () => {
+		const screen = await render(<SaveButton isDirty={true} isSaving={true} />);
+		await expect.element(screen.getByText("Saving...")).toBeInTheDocument();
+		await expect.element(screen.getByRole("button")).toBeDisabled();
+	});
+
+	it("shows 'Saved' when not dirty and not saving", async () => {
+		const screen = await render(<SaveButton isDirty={false} isSaving={false} />);
+		await expect.element(screen.getByText("Saved")).toBeInTheDocument();
+		await expect.element(screen.getByRole("button")).toBeDisabled();
+	});
+
+	it("has aria-busy when saving", async () => {
+		const screen = await render(<SaveButton isDirty={true} isSaving={true} />);
+		await expect.element(screen.getByRole("button")).toHaveAttribute("aria-busy", "true");
+	});
+
+	it("does not have aria-busy when not saving", async () => {
+		const screen = await render(<SaveButton isDirty={true} isSaving={false} />);
+		await expect.element(screen.getByRole("button")).toHaveAttribute("aria-busy", "false");
+	});
+
+	it("has aria-live polite", async () => {
+		const screen = await render(<SaveButton isDirty={true} isSaving={false} />);
+		await expect.element(screen.getByRole("button")).toHaveAttribute("aria-live", "polite");
+	});
+
+	it("respects external disabled prop", async () => {
+		const screen = await render(<SaveButton isDirty={true} isSaving={false} disabled={true} />);
+		await expect.element(screen.getByRole("button")).toBeDisabled();
+	});
+});