Run buildEnd after prerendering

[brophdawg11]

Summary

• move the React Router config buildEnd hook to run after the prerender plugin completes
• keep buildEnd args unchanged and close plugin resources from the final build wrapper
• add a prerender regression test that verifies buildEnd can see generated HTML/data files

Closes #15206

Testing

• pnpm test:integration:run integration/vite-prerender-test.ts --project chromium -g "Runs buildEnd after prerendering is complete"
• pnpm test:integration:run integration/vite-presets-test.ts --project chromium

[github-actions]

Preview Build Available

Preview builds have been created for this PR. You can install react-router using:

pnpm install "remix-run/react-router#preview/pr-15211&path:packages/react-router"

And/or install other packages via:

pnpm install "remix-run/react-router#preview/pr-15211&path:packages/react-router-dev"
pnpm install "remix-run/react-router#preview/pr-15211&path:packages/react-router-express"
pnpm install "remix-run/react-router#preview/pr-15211&path:packages/react-router-node"
pnpm install "remix-run/react-router#preview/pr-15211&path:packages/react-router-serve"

These preview builds will be updated automatically as you push new commits.

[github-actions]

✅ Change File Found

A change file file exists in this PR. Thanks!