Adding MongoDB setup instructions

Author: ajosh0504

docs/10-key-concepts/_category_.json

@@ -1,6 +1,6 @@
 {
   "label": "Key Concepts",
-  "position": 1,
+  "position": 10,
   "link": {
     "type": "generated-index",
     "description": "Learn the basics of AI agents"

docs/20-getting-started/1-mongodb-setup.mdx

@@ -0,0 +1,8 @@
+{
+    "label": "MongoDB Atlas",
+    "position": 20,
+    "link": {
+        "type": "generated-index",
+        "description": "Create a MongoDB Atlas account and deploy a free cluster"
+    }
+}

docs/20-getting-started/_category_.json

@@ -0,0 +1,8 @@
+{
+    "label": "Dev Environment",
+    "position": 30,
+    "link": {
+        "type": "generated-index",
+        "description": "Setup the dev environment and prerequisites"
+    }
+}