feat(landing): migrate from Next.js to Astro 5

Zero client JS, 165 static pages, self-hosted fonts, Otter Orange
design system. Includes tool SEO data for all 157 tools, enterprise
page, and updated e2e landing tests.

apps/landing/astro.config.mjs

@@ -0,0 +1,23 @@
+import { defineConfig } from "astro/config";
+import tailwindcss from "@tailwindcss/vite";
+import sitemap from "@astrojs/sitemap";
+
+export default defineConfig({
+  site: "https://snapotter.com",
+  output: "static",
+  integrations: [
+    sitemap({
+      filter: (page) => !page.includes("/404"),
+    }),
+  ],
+  vite: {
+    plugins: [tailwindcss()],
+    resolve: {
+      extensions: [".ts", ".tsx", ".js", ".jsx"],
+      conditions: ["import", "module"],
+    },
+  },
+  build: {
+    format: "directory",
+  },
+});