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+# Svelte validation rewrites the live dev server route manifest
+
+While investigating shared sidebar leakage, running `svelte-check --tsconfig ./tsconfig.json` in `web/workspace` rewrote every file under `.svelte-kit/generated`, even though no routes had been added or removed. The live Vite server watches the same directory and reacted with repeated full-page reloads for all generated node modules.
+
+The failure is more severe than reload noise. During the rewrite, Vite retained module transforms keyed by the previous generated node numbers. Subsequent hard reloads hydrated routes with unrelated layouts; for example, `/design-lab/workspace-web-ux` attempted to hydrate `src/routes/w/[workspaceId]/settings/+layout.svelte`, issued requests containing `undefined` route parameters, and failed with a DOM hierarchy error. The generated files on disk were internally consistent after the command completed, but the running dev server remained inconsistent until restarted.
+
+This is reproducible in an isolated copy: after `svelte-kit sync`, recording `.svelte-kit/generated` mtimes and then running `svelte-check` shows that the checker rewrites the generated route tree. `vite build` also uses the same `.svelte-kit` directory.
+
+For this investigation, validation was moved to `target/yoi-web-validation`, with the current source copied there and the existing `node_modules` linked in. `svelte-kit sync`, `svelte-check`, production build, and browser route-transition checks then ran without mutating the live server's output.
+
+Suggested improvement: make repository Web validation use an isolated SvelteKit `outDir` or a disposable copied workspace by default. Validation commands must not share `.svelte-kit` with a running dev server. Vite could also ignore generated route churn that it owns, but isolation is the stronger contract because build and check rewrite the files non-atomically.