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/core/tests/integration/mcp/harness-smoke.test.ts

@@ -0,0 +1,72 @@
+/**
+ * Smoke test for the MCP integration harness.
+ *
+ * Verifies the `connectMcpHarness()` plumbing is sound: real DB, real
+ * runtime, real MCP client/server pair. This is not bug coverage — it
+ * just guards against regressions in the harness itself. Bug-specific
+ * tests live in the other files in this directory.
+ */
+
+import { Role } from "@emdash-cms/auth";
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+
+import { connectMcpHarness, extractJson, type McpHarness } from "../../utils/mcp-runtime.js";
+import { setupTestDatabaseWithCollections, teardownTestDatabase } from "../../utils/test-db.js";
+
+describe("MCP harness smoke", () => {
+	let harness: McpHarness;
+	let dbCleanup: () => Promise<void>;
+
+	beforeEach(async () => {
+		const db = await setupTestDatabaseWithCollections();
+		harness = await connectMcpHarness({
+			db,
+			userId: "user_admin",
+			userRole: Role.ADMIN,
+		});
+		dbCleanup = () => teardownTestDatabase(db);
+	});
+
+	afterEach(async () => {
+		await harness.cleanup();
+		await dbCleanup();
+	});
+
+	it("exposes registered MCP tools via tools/list", async () => {
+		const tools = await harness.client.listTools();
+		const names = tools.tools.map((t) => t.name);
+		expect(names).toContain("content_list");
+		expect(names).toContain("content_create");
+		expect(names).toContain("schema_list_collections");
+	});
+
+	it("can call schema_list_collections and get the seeded test collections", async () => {
+		const result = await harness.client.callTool({
+			name: "schema_list_collections",
+			arguments: {},
+		});
+		expect(result.isError).toBeFalsy();
+		const { items } = extractJson<{ items: Array<{ slug: string }> }>(result);
+		const slugs = items.map((c) => c.slug);
+		expect(slugs).toContain("post");
+		expect(slugs).toContain("page");
+	});
+
+	it("can round-trip a simple content_create + content_get", async () => {
+		const created = await harness.client.callTool({
+			name: "content_create",
+			arguments: { collection: "post", data: { title: "Hello" } },
+		});
+		expect(created.isError).toBeFalsy();
+		const createdItem = extractJson<{ item: { id: string; slug: string } }>(created);
+
+		const got = await harness.client.callTool({
+			name: "content_get",
+			arguments: { collection: "post", id: createdItem.item.id },
+		});
+		expect(got.isError).toBeFalsy();
+		const gotItem = extractJson<{ item: { id: string; slug: string } }>(got);
+		expect(gotItem.item.id).toBe(createdItem.item.id);
+		expect(gotItem.item.slug).toBe("hello");
+	});
+});