Migrate from Deno/JSR to npm publishing

- @sveltejs/package builds dist/ for @eeeooolll/graphiql with three entry
  points (./, ./component, ./splitter)
- Vitest + svelte-check replace Deno test/check; runes shim no longer
  needed since the Svelte plugin compiles .svelte.ts at runtime
- Drop $app/environment dep in Editor.svelte to support non-SvelteKit
  consumers
- Refactor TabBar tab element from nested <button> to role=tab <div> per
  PLAN.md gotcha; svelte-check flagged the invalid HTML
- README now documents npm install, integration patterns for Yoga,
  Apollo, graphql-modules, Hono/Bun/Deno, plus APQ + keyboard table

1 files changed, 10 insertions, 0 deletions

diff --git a/vitest.config.ts b/vitest.config.ts
new file mode 100644
index 0000000..c24a061
--- /dev/null
+++ b/vitest.config.ts
@@ -0,0 +1,10 @@
+import { svelte } from "@sveltejs/vite-plugin-svelte";
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  plugins: [svelte({ hot: false })],
+  test: {
+    environment: "node",
+    include: ["tests/**/*.test.ts"]
+  }
+});