Add Vite playground for local development

npm run dev boots a Vite + Svelte 5 server at localhost:5173, importing
GraphiQL.svelte directly from source/library. HMR reflects changes
without a package rebuild. Points at the public Countries API by default
— swap playground/src/App.svelte for your own endpoint.

1 files changed, 3 insertions, 0 deletions

diff --git a/.npmignore b/.npmignore
index 51dd034..f1b7da2 100644
--- a/.npmignore
+++ b/.npmignore
@@ -1,6 +1,9 @@
 source/
 tests/
+playground/
 PLAN.md
 .gitignore
 svelte.config.js
 tsconfig.json
+vite.config.ts
+vitest.config.ts