add groundedness to index

Author: PatrickFarley

articles/ai-services/content-safety/index.yml

@@ -57,12 +57,16 @@ landingContent:
         links:
           - text: Harm categories
             url: concepts/harm-categories.md
+          - text: Groundedness detection
+            url: concepts/groundedness.md
       - linkListType: quickstart
         links:
           - text: Using Content Safety Studio
             url: studio-quickstart.md?pivots=content-safety-studio
           - text: Using the REST API or client SDKs
             url: quickstart-text.md?pivots=programming-language-rest
+          - text: Detect groundedness in LLM responses
+            url: quickstart-groundedness.md
       - linkListType: how-to-guide
         links:
           - text: Use a blocklist