Scaffold Astro/Strapi monorepo for the site rebuild

Set up a pnpm workspace with apps/site (Astro) and apps/cms (Strapi,
SQLite-backed) as the foundation for the new digital-legacy site.
Switches package management to pnpm and adds Biome for linting/
formatting, replacing npm/no-linter setup. Existing Zola site stays
in place for now and will be migrated/removed progressively.

apps/cms/src/index.ts

@@ -0,0 +1,20 @@
+// import type { Core } from '@strapi/strapi';
+
+export default {
+  /**
+   * An asynchronous register function that runs before
+   * your application is initialized.
+   *
+   * This gives you an opportunity to extend code.
+   */
+  register(/* { strapi }: { strapi: Core.Strapi } */) {},
+
+  /**
+   * An asynchronous bootstrap function that runs before
+   * your application gets started.
+   *
+   * This gives you an opportunity to set up your data model,
+   * run jobs, or perform some special logic.
+   */
+  bootstrap(/* { strapi }: { strapi: Core.Strapi } */) {},
+};