feat(docs): rename and restructure getting started content

- Rename 'introduction.mdx' to 'getting-started.mdx'
- Update title to 'Getting Started: Local Setup'
- Modify internal links to point to new locations:
  - API setup guide
  - Dashboard setup guide
  - Mobile app setup guide

Author: fulleni

src/content/docs/introduction.mdx renamed to src/content/docs/getting-started.mdx

@@ -1,5 +1,5 @@
 ---
-title: Local Setup Guide
+title: 'Getting Started: Local Setup'
 description: An overview of the local setup process for the entire Flutter News App ecosystem.
 ---
 
@@ -12,19 +12,19 @@ Follow the guides below in the recommended order to ensure a smooth setup proces
 <CardGrid>
   <Card title="1. Set Up the API Server" icon="cloud">
     Start by getting the backend running. The API server handles data, authentication, and configuration for both the dashboard and the mobile app.
-    <a href="/getting-started/local-setup-api" style={{ display: 'block', marginTop: '1rem' }}>
+    <a href="/api-server/local-setup/" style={{ display: 'block', marginTop: '1rem' }}>
       Go to API Setup Guide &rarr;
     </a>
   </Card>
   <Card title="2. Set Up the Web Dashboard" icon="laptop">
     Next, run the web-based administrative dashboard. You'll use this to manage content and configure the application.
-    <a href="/getting-started/local-setup-dashboard" style={{ display: 'block', marginTop: '1rem' }}>
+    <a href="/web-dashboard/local-setup/" style={{ display: 'block', marginTop: '1rem' }}>
       Go to Dashboard Setup Guide &rarr;
     </a>
   </Card>
   <Card title="3. Set Up the Mobile Client" icon="phone">
     Finally, set up the Flutter mobile app for iOS and Android to see the end-user experience.
-    <a href="/getting-started/local-setup-mobile" style={{ display: 'block', marginTop: '1rem' }}>
+    <a href="/mobile-client/local-setup/" style={{ display: 'block', marginTop: '1rem' }}>
       Go to Mobile App Setup Guide &rarr;
     </a>
   </Card>