Add new integration tiles for Mastra, CrewAI, and LangGraph

Author: MQ37

sources/platform/integrations/index.mdx

@@ -150,13 +150,31 @@ If you are working on an AI/LLM-related project, we recommend you look into the
 
 <CardGrid>
     <Card
-        title="Langchain"
+        title="Mastra"
+        to="./integrations/mastra"
+        imageUrl="/img/platform/integrations/mastra.png"
+        smallImage
+    />
+    <Card
+        title="CrewAI"
+        to="./integrations/crewai"
+        imageUrl="/img/platform/integrations/crewai.png"
+        smallImage
+    />
+    <Card
+        title="LangGraph"
+        to="./integrations/langgraph"
+        imageUrl="/img/platform/integrations/langgraph.png"
+        smallImage
+    />
+    <Card
+        title="LangChain"
         to="./integrations/langchain"
         imageUrl="/img/platform/integrations/langchain.png"
         smallImage
     />
     <Card
-        title="Llamaindex"
+        title="LlamaIndex"
         to="./integrations/llama"
         imageUrl="/img/platform/integrations/llamaindex.jpeg"
         smallImage