docs: enrich landing pages (#2165)

Signed-off-by: Panos Vagenas <pva@zurich.ibm.com>

docs/integrations/index.md

@@ -1,6 +1,19 @@
-Use the navigation on the left to browse through Docling integrations with popular frameworks and tools.
+In this space, you can explore various Docling integrations with leading frameworks and tools!
 
+Here some of our picks to get you started:
 
-<p align="center">
-  <img loading="lazy" alt="Docling" src="../assets/docling_ecosystem.png" width="100%" />
-</p>
+- [🦜️🔗 LangChain](./langchain.md)
+- [༄ Langflow](./langflow.md)
+- [🦙 LlamaIndex](./llamaindex.md)
+- [🌾 Haystack](./haystack.md)
+- [🇨 Crew AI](./crewai.md)
+
+👈 ... and there is much more: explore all integrations using the navigation menu on the side
+
+<div class="grid" style="text-align: center">
+    <div class="card">
+        <img loading="lazy" alt="Part of Docling's ecosystem" src="../assets/docling_ecosystem.png" width="75%" />
+        <hr />
+        A glimpse into Docling's ecosystem
+    </div>
+</div>