docs: add workflow run filters to list messages endpoint (#768)

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: Christopher Bell <chris@knock.app>

content/reference.mdx

@@ -1047,6 +1047,16 @@ Messages outside the account's retention window will not be included in the resu
     type="string[] (optional)"
     description="Limits the results to only items related to any of the provided categories"
   />
+  <Attribute
+    name="workflow_run_id"
+    type="string (optional)"
+    description="Limits the results to messages triggered by the top-level workflow run ID"
+  />
+  <Attribute
+    name="workflow_recipient_run_id"
+    type="string (optional)"
+    description="Limits the results to messages for a specific recipient's workflow run"
+  />
   <Attribute
     name="trigger_data"
     type="JSON string (optional)"