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

templates/starter/tsconfig.json

@@ -0,0 +1,7 @@
+{
+	"extends": "astro/tsconfigs/base",
+	"compilerOptions": {
+		"types": ["node"]
+	},
+	"include": ["src", ".astro/types.d.ts", "emdash-env.d.ts"]
+}