fix(dashboard): apply mobile scroll lock during inline edits, not just modals

Inline editing on the dashboard (e.g. TaskCard inline edit) doesn't go
through a modal, so it didn't get useMobileScrollLock applied. iOS would
shift the visualViewport / window scroll for the focused input and
sometimes leave the dashboard pushed up after the keyboard dismissed.

App.tsx now activates useMobileScrollLock whenever mobileKeyboardOpen is
true (mobile + keyboard up + no modal open). Modals continue to manage
their own lock; the hook is reference-counted so they don't conflict.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/dashboard/app/App.tsx

@@ -42,6 +42,7 @@ import { useDeepLink } from "./hooks/useDeepLink";
 import { useFavorites } from "./hooks/useFavorites";
 import { useAuthOnboarding } from "./hooks/useAuthOnboarding";
 import { useMobileKeyboard } from "./hooks/useMobileKeyboard";
+import { useMobileScrollLock } from "./hooks/useMobileScrollLock";
 import { useSetupReadiness } from "./hooks/useSetupReadiness";
 import { useUpdateCheck } from "./hooks/useUpdateCheck";
 import { useViewState, type TaskView } from "./hooks/useViewState";
@@ -292,6 +293,12 @@ function AppInner() {
   // viewport. Without this guard, modal keyboard state leaks into the app-level
   // layout, causing stale bottom-padding offsets after the keyboard closes.
   const mobileKeyboardOpen = isMobile && keyboardOpen && !modalManager.anyModalOpen;
+  // App-level scroll lock for inline editing (TaskCard inline edit, etc.):
+  // when the keyboard is up outside of any modal, pin the body so iOS can't
+  // shift the document or visualViewport, and so the dashboard snaps back
+  // into place when the keyboard dismisses. Modals manage their own lock
+  // via useMobileScrollLock — the reference-counted hook handles overlap.
+  useMobileScrollLock(mobileKeyboardOpen);
 
   // App-level mailbox unread count state (used for header/mobile nav badges)
   const [mailboxUnreadCount, setMailboxUnreadCount] = useState(0);