fix(email-renderer): preserve valid column table structure

packages/email-renderer/test/email.test.ts

@@ -73,6 +73,41 @@ describe("email renderer", () => {
     expect((await validateAmpEmail("<html></html>")).valid).toBe(false);
   });
 
+  test("keeps rendered block rows inside valid column tables", async () => {
+    const columnDocument = structuredClone(document);
+    const content = columnDocument.root.slots.content[0]!.slots.content;
+    columnDocument.root.slots.content[0]!.slots.content = [
+      {
+        id: "columns",
+        type: "layout.columns",
+        version: 1,
+        props: {},
+        styles: {},
+        slots: {
+          columns: [
+            {
+              id: "column",
+              type: "layout.column",
+              version: 1,
+              props: { width: "100%" },
+              styles: {},
+              slots: { content },
+            },
+          ],
+        },
+      },
+    ];
+    const rendered = await renderEmail(columnDocument, { amp: true });
+    expect(rendered.ok).toBe(true);
+    if (!rendered.ok) return;
+    expect(rendered.value.parts.html.content).toContain(
+      'data-block-id="column" class="wrn-column" width="100%" valign="top"><table role="presentation"',
+    );
+    expect(rendered.value.parts.html.content).toContain(
+      '<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0"><tr><td data-block-id="heading"',
+    );
+  });
+
   test("compiles only allowlisted semantic styles", async () => {
     const styled = structuredClone(document);
     styled.root.slots.content[0]!.slots.content[0]!.styles = {