* fix: exclude vinext from optimizeDeps to prevent virtual module resolution errors
When vinext is installed from npm (not symlinked), esbuild's dependency
optimization scans vinext/dist/ and hits virtual:vinext-* imports that
only exist at Vite plugin resolution time. This causes build failures
in all three environments (client, rsc, ssr).
Adding optimizeDeps.exclude: ['vinext'] at the top level and in each
environment prevents esbuild from scanning vinext's dist files entirely.
Fixes#1
* test: verify optimizeDeps.exclude contains vinext for all environments
Sunil Pai