Dev server startup perf

[koculu]

Summary

Improve PureStack dev-server startup performance by switching the default serve workflow from a full initial build to render-on-request.

The server now prepares shared state such as routes and navigation at startup, then renders pages and copies assets only when they are requested.

Changes

• Render pages lazily on first request and cache the generated output.
• Copy static assets only when requested.
• Invalidate affected pages and script bundles on file changes instead of rebuilding them immediately.
• Re-render invalidated pages on their next request.
• Add --full-render / fullRender: true to preserve the previous full-build-at-startup behavior when needed.
• Build the development Pagefind index from pages rendered during the current session.
  • --full-render, build, and publish still generate the complete search index.
• Improve request handling for:
  • hidden-locale i18n routes
  • encoded URLs
  • direct index.html requests
  • extensionless assets
  • static directories
• Handle edits that occur while a page is already being rendered without losing invalidation state.
• Expand dev-server tests around lazy rendering, assets, watched changes, Pagefind, i18n, and full-render mode.
• Update CLI and documentation for the new behavior.
• Bump packages to 1.1.4 and update Vite/Vitest dependencies.

Result

purestack serve can become ready without compiling every page in the site, substantially reducing startup work for larger projects while keeping full static generation available through --full-render.