windows stop flush with the taskbar's top edge instead of tucking 6px under it

opencode.md

@@ -227,7 +227,10 @@ list reordering, not free placement. Don't confuse the two.
   `moveWin` clamps `x`/`y` (dragging can't push a window off any edge or under
   the panel), a `resize` effect re-clamps on browser resize, and
   `.win-window.centered` carries `max-width`/`max-height`. Keep these in sync if
-  you add a new window path, or windows will escape the viewport.
+  you add a new window path, or windows will escape the viewport. The bottom
+  limit is `TASKBAR_HEIGHT = 54` in `WindowsDesktop.tsx` (panel `bottom:10px` +
+  `height:44px`), so a window lands flush with the panel's top edge; note
+  `useDesktopIcons.ts` has its **own** `TASKBAR_HEIGHT = 48` for the icon grid.
 - Exposing the **dev** server over a tunnel needs the tunnel host in
   `allowedDevOrigins` (`next.config.ts`). Without it Next dev rejects the
   cross-origin HMR WebSocket, so the client never hydrates — the page is SSR

src/app/components/WindowsDesktop.tsx

@@ -9,7 +9,11 @@ import { useTheme } from "./useTheme";
 import { useDesktopIcons } from "./useDesktopIcons";
 import { WALLPAPER, friends } from "../data";
 
-const TASKBAR_HEIGHT = 48;
+// The panel is anchored at `bottom: 10px` and is 44px tall, so the usable
+// desktop area ends 54px above the viewport bottom. Windows are clamped to that
+// line, so a window dragged down lands flush with the top of the taskbar with
+// nothing hidden behind it.
+const TASKBAR_HEIGHT = 54;
 
 const LEFT_APPS = APPS.filter((a) => a.id !== "services" && a.id !== "friends");