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/fixture/package.json

@@ -0,0 +1,16 @@
+{
+	"name": "emdash-integration-fixture",
+	"private": true,
+	"type": "module",
+	"dependencies": {
+		"@astrojs/node": "catalog:",
+		"@astrojs/react": "catalog:",
+		"@emdash-cms/auth": "workspace:*",
+		"@emdash-cms/plugin-color": "workspace:*",
+		"astro": "catalog:",
+		"better-sqlite3": "^11.10.0",
+		"emdash": "workspace:*",
+		"react": "^19.1.0",
+		"react-dom": "^19.1.0"
+	}
+}