docs: add Analytics API reference documentation (#627)

* docs: add Analytics API reference documentation

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

* fix: use snake_case for pagination fields (has_more, next_cursor)

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

---------

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

Author: nikhil-factory

docs/docs.json

@@ -155,7 +155,7 @@
               },
               {
                 "group": "Analytics & Operations",
-                "pages": ["enterprise/usage-cost-and-analytics"]
+                "pages": ["enterprise/usage-cost-and-analytics", "reference/analytics-api"]
               }
             ]
           },