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

infra/perf-monitor/vite.config.ts

@@ -0,0 +1,29 @@
+import { cloudflare } from "@cloudflare/vite-plugin";
+import { defineConfig } from "vite";
+
+const PROBE_REGIONS = [
+	{ id: "use", region: "aws:us-east-1" },
+	{ id: "euw", region: "aws:eu-west-2" },
+	{ id: "ape", region: "aws:ap-northeast-1" },
+	{ id: "aps", region: "aws:ap-southeast-1" },
+] as const;
+
+export default defineConfig({
+	plugins: [
+		cloudflare({
+			configPath: "./wrangler.jsonc",
+			auxiliaryWorkers: PROBE_REGIONS.map((probe) => ({
+				config: (_, { entryWorkerConfig }) => ({
+					name: `emdash-perf-probe-${probe.id}`,
+					main: "./probe/src/index.ts",
+					account_id: entryWorkerConfig.account_id,
+					compatibility_date: entryWorkerConfig.compatibility_date,
+					compatibility_flags: entryWorkerConfig.compatibility_flags,
+					placement: {
+						region: probe.region,
+					},
+				}),
+			})),
+		}),
+	],
+});