fix hydration mismatch: sync html data-scheme default to dark and suppress body attribute warnings

agents.md

@@ -34,7 +34,7 @@ When in doubt, prefer updating. A stale README **or** agents.md is treated as a
 ## Bump the version on EVERY prompt — also do this every time
 
 Another standing requirement: increment the **patch** version (`x.x.+1`, so
-`2.2.6` → `2.2.7` → …) as part of every task, even the small ones. Keep all of
+`2.2.7` → `2.2.8` → …) as part of every task, even the small ones. Keep all of
 these in sync:
 
 - `package.json` → `"version"`
@@ -56,7 +56,7 @@ frosted-glass **web** site, and an alternate KDE/Plasma **desktop simulation**
   utilities in the components (Tailwind is present via PostCSS but the look is
   hand-written CSS).
 - Path alias: `@/*` → `src/*`.
-- Version: `2.2.7` (see `package.json`).
+- Version: `2.2.8` (see `package.json`).
 
 ### Scripts
 ```bash
@@ -124,6 +124,11 @@ scripts/
    `localStorage.scheme` and sets `data-scheme` (`light` | `dark`), defaulting to
    `dark` (only an explicit stored `light` overrides it). There is no device
    sniff anymore.
+   **Keep `layout.tsx`'s server-rendered `<html>` defaults in sync** (`data-theme="web"`,
+   `data-scheme="dark"`) with this script's defaults, or React 19 logs a hydration
+   attribute mismatch ("A tree hydrated but some attributes… didn't match"). `<html>`
+   and `<body>` both carry `suppressHydrationWarning` (the theme script mutates `<html>`
+   before hydration, and browser extensions mutate `<body>`).
 2. `useTheme()` (in `useTheme.ts`) reads `data-theme` via `useSyncExternalStore`
    and dispatches a `theme-change` event on toggle. `useColorScheme()` does the
    same for `data-scheme` via a `scheme-change` event.
@@ -454,7 +459,7 @@ knows about icon ids, via `APP_BY_ID`.
 - There is **no test suite**. Verification is `tsc --noEmit`, `eslint`, and
   `next build`.
 - The default shell is the web theme: `curl -s http://localhost:3000/` should
-  contain `data-theme="web"` / `data-scheme="light"` and the `.web-root` markup.
+  contain `data-theme="web"` / `data-scheme="dark"` and the `.web-root` markup.
   Theme + scheme are read pre-paint from `localStorage.theme` / `.scheme`, so a
   quick check is to set those in devtools and reload.
 - `next/image` is lazy by default, so a headless full-page screenshot shows the