feat: generate redirects in Astro

The only thing I couldn't get working were `articles/*` to `blog/*`
redirects, but those haven't been used for a long time and can be
re-attempted another time.

astro.config.mjs

@@ -1,9 +1,9 @@
-import { defineConfig } from "astro/config";
 import alpinejs from "@astrojs/alpinejs";
-import tailwind from "@astrojs/tailwind";
 import mdx from "@astrojs/mdx";
-
+import redirects from "./redirects.json";
 import sitemap from "@astrojs/sitemap";
+import tailwind from "@astrojs/tailwind";
+import { defineConfig } from "astro/config";
 
 // https://astro.build/config
 export default defineConfig({
@@ -16,13 +16,14 @@ export default defineConfig({
         // otherwise it will be a link to a redirect URL and not the content.
         item.url = item.url.replace(/\/$/, "");
         return item;
-      }
+      },
     }),
     tailwind({
       config: {
-        applyBaseStyles: false
-      }
+        applyBaseStyles: false,
+      },
     }),
   ],
-  site: "https://www.oliverdavies.uk"
+  redirects,
+  site: "https://www.oliverdavies.uk",
 });