fix: use full tag path in drag-drop toasts, fresh email in context menu markAsRead

Nested tag toasts from drag-and-drop only showed the leaf name for
non-root tags, contradicting the comment above it and making two
same-named leaves under different parents (e.g. Personal/Receipts vs
Work/Receipts) indistinguishable in the toast.

The context menu's markAsRead handler was the one action left reading
the stale contextMenu.data instead of the live-refreshed
contextMenuEmail introduced alongside it, so it could act on outdated
email state while every sibling handler was already updated.

components/email/email-list.tsx

@@ -598,7 +598,7 @@ export function EmailList({
           onReplyAll={() => onReplyAll?.(contextMenuEmail!)}
           onForward={() => onForward?.(contextMenuEmail!)}
           onForwardAsAttachment={() => onForwardAsAttachment?.(contextMenuEmail!)}
-          onMarkAsRead={(read) => onMarkAsRead?.(contextMenu.data!, read)}
+          onMarkAsRead={(read) => onMarkAsRead?.(contextMenuEmail!, read)}
           onToggleStar={() => onToggleStar?.(contextMenuEmail!)}
           onTogglePinned={onTogglePinned ? () => onTogglePinned(contextMenuEmail!) : undefined}
           onDelete={() => onDelete?.(contextMenuEmail!)}