Add page for count_and_keep_open

Author: Fayti1703

docs/scripting/db/cursor/count_and_keep_open.mdx

@@ -0,0 +1,24 @@
+Retrieve the total number of documents of the cursor, keeping it open.
+
+This method ignores `skip` and `limit` settings.
+
+## Syntax
+
+```
+let cursor = #db.f(query, projection)
+cursor.count_and_keep_open()
+```
+
+### Parameters
+
+No parameters.
+
+### Return
+
+The total number of documents of this cursor, as a number.
+
+## Cursor State
+
+This function keeps the cursor open.
+
+Try [count](./count) for a variant of this function that automatically closes the cursor.