fix(ci): terminal required workaround

.github/workflows/ci.yaml

@@ -10,6 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     env:
       PROJECT_NAME: basic-tests
+      CARGO_GENERATE_VALUE_CI: true
     steps:
       - name: Checkout sources
         uses: actions/checkout@v4

cargo_generate_hooks/init.rhai

@@ -1,3 +1,10 @@
+// WORKAROUND:
+// CI will otherwise fail with a `Runtime error: IO error: not a terminal`,
+// even when returning early for predefined values.
+if variable::is_set("CI") {
+	exit();
+}
+
 template_book();
 template_precommit_hooks();
 prompt_optional_string("codecov", "Codecov token");