fix(core): remove empty index page to prevent blank docs page

This removes the empty markdown file that were previously added by
`ensureAstroCollectionNotEmpty` when no index page was specified by
the user. This introduce `default-docs.mdx` as fallback to prevent
blank /docs page. This approach ensures a better UX without redirecting
to the first collection item, as an initial empty project may not have
any items to navigate to.

Closes event-catalog#1130.

eventcatalog/src/pages/docs/[type]/[id]/[version]/spec/index.astro

@@ -4,7 +4,6 @@ import * as path from 'path';
 import fs from 'node:fs';
 
 import type { CollectionTypes, PageTypes } from '@types';
-import PlainPage from '@layouts/PlainPage.astro';
 import { DocumentMinusIcon } from '@heroicons/react/24/outline';
 import { buildUrl } from '@utils/url-builder';
 import { pageDataLoader } from '@utils/page-loaders/page-data-loader';

eventcatalog/src/pages/docs/_default-docs.mdx

@@ -0,0 +1,24 @@
+# **EventCatalog**
+
+Welcome to [EventCatalog](https://www.eventcatalog.dev/).
+
+This open-source project is designed to help you and your teams bring discoverability and clarity to your event-driven architectures (EDA).
+
+To get started you can read the following guides:
+
+- [Getting started with EventCatalog](https://eventcatalog.dev/docs/development/getting-started/introduction)
+- [Creating domains](https://eventcatalog.dev/docs/development/guides/domains/adding-domains)
+- [Creating services](https://eventcatalog.dev/docs/development/guides/services/adding-services)
+- [Creating commands](https://eventcatalog.dev/docs/development/guides/messages/commands/introduction)
+- [Creating events](https://eventcatalog.dev/docs/development/guides/messages/events/introduction)
+- [Assigning owners to resources](https://eventcatalog.dev/docs/owners)
+- [Using components in your pages (Schemas, OpenAPI, etc)](https://eventcatalog.dev/docs/development/components/using-components)
+- [Deploying and hosting your EventCatalog](https://eventcatalog.dev/docs/development/deployment)
+
+### **Join the community**
+
+Got questions about EventCatalog? Feature requests or need support? [Join our community on Discord.](https://discord.gg/3rjaZMmrAm)
+
+### **Enterprise support**
+
+Using EventCatalog and needs enterprise support? Work with us, find out what we offer on our [enterprise page](https://eventcatalog.dev/enterprise).

eventcatalog/src/pages/docs/index.astro

@@ -1,6 +1,5 @@
 ---
 import Footer from '@layouts/Footer.astro';
-import DefaultDocsLandingPage from '@layouts/CustomDocsPageLayout.astro';
 import components from '@components/MDX/page-components';
 import { getIndexPage } from '@utils/pages';
 import VerticalSideBarLayout from '@layouts/VerticalSideBarLayout.astro';
@@ -11,24 +10,20 @@ let CustomContent = null;
 if (page) {
   const { Content } = await page.render();
   CustomContent = Content;
+} else {
+  CustomContent = await import('./_default-docs.mdx').then((mod) => mod.default);
 }
 ---
 
-{
-  CustomContent && (
-    <VerticalSideBarLayout title="EventCatalog">
-      <main class="flex sm:px-8 docs-layout h-full">
-        <div class="flex docs-layout w-full">
-          <div class="w-full lg:mr-2 pr-8 overflow-y-auto py-8">
-            <div class="prose prose-md w-full !max-w-none">
-              <CustomContent components={components} />
-            </div>
-            <Footer />
-          </div>
+<VerticalSideBarLayout title="EventCatalog">
+  <main class="flex sm:px-8 docs-layout h-full">
+    <div class="flex docs-layout w-full">
+      <div class="w-full lg:mr-2 pr-8 overflow-y-auto py-8">
+        <div class="prose prose-md w-full !max-w-none">
+          <CustomContent components={components} />
         </div>
-      </main>
-    </VerticalSideBarLayout>
-  )
-}
-
-{!CustomContent && <DefaultDocsLandingPage title="EventCatalog" />}
+        <Footer />
+      </div>
+    </div>
+  </main>
+</VerticalSideBarLayout>