fix(desktop): persist mocked voice settings

Signed-off-by: John Tennant <jtennant@squareup.com>

desktop/src/testing/e2eBridge.ts

@@ -9737,7 +9737,10 @@ export function maybeInstallE2eTauriMocks() {
           voicePreferences: activeConfig?.mock?.ttsSettings
             ?.voicePreferences ?? ["pocket:mary"],
         };
-        if (activeConfig?.mock) activeConfig.mock.ttsSettings = settings;
+        if (activeConfig) {
+          activeConfig.mock ??= {};
+          activeConfig.mock.ttsSettings = settings;
+        }
         return settings;
       }
       case "set_pocket_voice": {
@@ -9760,7 +9763,10 @@ export function maybeInstallE2eTauriMocks() {
           voiceKey,
         );
         const settings = { ...current, voicePreferences: preferences };
-        if (activeConfig?.mock) activeConfig.mock.ttsSettings = settings;
+        if (activeConfig) {
+          activeConfig.mock ??= {};
+          activeConfig.mock.ttsSettings = settings;
+        }
         return settings;
       }
       case "preview_pocket_voice":

desktop/tests/e2e/voice-settings.spec.ts

@@ -29,6 +29,9 @@ test.describe("Pocket voice settings", () => {
     );
 
     await page.getByTestId("agent-text-to-speech-toggle").click();
+    await expect(
+      page.getByTestId("agent-text-to-speech-toggle"),
+    ).toHaveAttribute("aria-checked", "false");
     await expect(page.getByTestId("pocket-voice-controls")).toHaveAttribute(
       "aria-disabled",
       "true",