refactor: remove jsdom dependency from vitest config

The jsdom environment was configured but none of the unit tests use DOM
APIs — they all test pure logic (dependency graphs, content hashing, URL
paths, entry path validation). Switch to the default node environment
and remove the jsdom devDependency.

Closes #88

https://claude.ai/code/session_01MXf6zdcermnEnEYtCNES6K

Author: claude

packages/static/package.json

@@ -60,7 +60,7 @@
     "@types/node": "catalog:",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
-    "jsdom": "^29.0.1",
+
     "react": "catalog:",
     "react-dom": "catalog:",
     "tsdown": "^0.21.4",

packages/static/src/__tests__/vitest.setup.ts

@@ -2,8 +2,6 @@ import { defineConfig } from "vitest/config";
 
 export default defineConfig({
   test: {
-    environment: "jsdom",
-    setupFiles: ["./src/__tests__/vitest.setup.ts"],
     globals: true,
     exclude: ["**/node_modules/**", "**/e2e/**"],
   },