fix(docs): hand-written meta descriptions on homepage + intro (#81)

Replace auto-generated meta descriptions on the highest-traffic
pages with hand-written, CTR-tuned variants. Part of the SEO epic
ConductionNL/.github#75.

Author: rubenvdlinde

docs/intro.md

@@ -1,5 +1,6 @@
 ---
 sidebar_position: 1
+description: Get started with OpenBuilt, the no-code app builder inside Nextcloud. Compose apps from OpenRegister schemas, OpenConnector flows, and Pipelinq.
 ---
 
 # OpenBuilt

docs/src/pages/index.js

@@ -233,7 +233,7 @@ export default function Home() {
   return (
     <Layout
       title="OpenBuilt, no-code app builder inside Nextcloud"
-      description="Citizen-developer app builder for Nextcloud — compose apps from registers, connectors, workflows, and documents without code."
+      description="Citizen-developer app builder for Nextcloud. Compose apps from registers, connectors, workflows, and documents without writing code."
     >
       <main className="marketing-page">
         <DetailHero