Render the table groups.

src/context/table_group.rs

@@ -0,0 +1,12 @@
+use super::table_row::RenderTableRow;
+use serde::Serialize;
+
+#[derive(Debug, Serialize)]
+#[serde(tag = "type")]
+pub(crate) enum RenderTableGroup {
+    #[serde(rename = "head")]
+    Head { children: Vec<RenderTableRow> },
+
+    #[serde(rename = "body")]
+    Body { children: Vec<RenderTableRow> },
+}