feat(blocks): add typed personalization resolution

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

@@ -90,6 +90,20 @@ describe("email renderer", () => {
     expect(rendered.value.parts.html.content).not.toContain("position:fixed");
   });
 
+  test("resolves allowlisted personalization values and fallbacks", async () => {
+    const personalized = structuredClone(document);
+    personalized.root.slots.content[0]!.slots.content[0]!.props.text =
+      "Hello {{recipientName|friend}}";
+    const rendered = await renderEmail(personalized, { variables: { recipientName: "Ada" } });
+    expect(rendered.ok && rendered.value.parts.html.content).toContain("Hello Ada");
+    const fallback = await renderEmail(personalized);
+    expect(fallback.ok && fallback.value.parts.text.content).toContain("Hello friend");
+    const strict = await renderEmail(personalized, { requireVariables: true });
+    expect(strict.ok).toBe(true);
+    personalized.root.slots.content[0]!.slots.content[0]!.props.text = "Hello {{recipientName}}";
+    expect((await renderEmail(personalized, { requireVariables: true })).ok).toBe(false);
+  });
+
   test("rejects unsafe MJML and imports supported content", () => {
     expect(
       importMjml("<mjml><mj-body><mj-raw>x</mj-raw></mj-body></mjml>", {