docs: fix config

packages/web/astro.config.mjs

@@ -33,6 +33,7 @@ export default defineConfig({
     solidJs(),
     starlight({
       title: "opencode",
+      lastUpdated: true,
       expressiveCode: { themes: ["github-light", "github-dark"] },
       social: [
         { icon: "github", label: "GitHub", href: config.github },

packages/web/src/content/docs/docs/config.mdx

@@ -5,7 +5,7 @@ description: Using the opencode JSON config.
 
 You can configure opencode using a JSON config file.
 
-```json title="opencode config"
+```json title="opencode.json"
 {
   "$schema": "https://opencode.ai/config.json",
   "theme": "opencode",