Three defects that together meant `npm run test:build` could not pass in any of
its four variants:
- svelte.config.js constructed adapter-netlify inline and never used the
`adapter` export from adapter.mjs, so NODE_ADAPTER=true still produced a flat
build/ directory while the build test expects the node adapter's build/client
layout. adapter.mjs now returns netlify (the deployment target) or node, and
svelte.config.js consumes it.
- No route is prerendered, so workbox's glob found no HTML document and a
generateSW build precached nothing navigable: the app had no offline support
in that mode at all. Adds the root entry and a navigation fallback, matching
what prompt-sw.ts already did by hand for injectManifest builds.
- The build scripts used by the tests skipped the tailwind step that `build`
runs, so static/output.css was never generated on a clean checkout and the
app under test had no stylesheet.
The offline entry point assertion now also accepts the unquoted object key that
prompt-sw.ts's own precache call survives minification as.
Josh Creek