feat: add net-zero badge (#32)

Reviewed-on: https://codeberg.org/nhcarrigan/docs/pulls/32
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

astro.config.mjs

@@ -4,7 +4,11 @@ import starlight from "@astrojs/starlight";
 import { navigation } from "./src/components/navigation.ts";
 
 export default defineConfig({
+  site: "https://docs.nhcarrigan.com",
   integrations: [starlight({
+    components: {
+      Footer: "./src/components/Footer.astro",
+    },
     title: "Naomi's Documentation",
     sidebar: navigation,
     tableOfContents: { minHeadingLevel: 2, maxHeadingLevel: 4},
@@ -43,6 +47,15 @@ export default defineConfig({
       {
         tag: "script",
         content: "window.plausible = window.plausible || function() { (window.plausible.q = window.plausible.q || []).push(arguments) }"
+      },
+      {
+        tag: "script",
+        attrs: {
+          type: "text/javascript",
+          id: "trees",
+          src: "https://widgets.tree-nation.com/js/widgets/v1/widgets.min.js?v=1.0",
+          defer: true
+        }
       }
     ],
     customCss: [