MSSettingsRow class

A single iOS-style settings list row.

Provides the standard anatomy shared by all settings rows in an iOS inset-grouped settings layout:

• Optional leading icon tile (9-unit square, rounded, surface-container-high background) wrapping a WIcon.
• Title text (semantic-token driven; tone-controlled via tone).
• Optional subtitle text below the title.
• A flexible trailing slot for any widget: Switch, Badge, value text, or a Button. The caller owns the trailing control; MSSettingsRow never hardcodes it.
• Minimum 44pt-equivalent height (min-h-11), horizontal px-5 py-3.5.
• Optional onTap to make the whole row tappable via WAnchor.

The row intentionally has no internal divider — the parent MSSettingsSection owns dividers between rows.

Default row (no icon, value trailing):

MSSettingsRow(
  title: 'Language',
  trailing: WText('English', className: 'text-sm text-fg-muted'),
)

Destructive row (Delete / Sign-out):

MSSettingsRow(
  title: 'Delete Account',
  tone: SettingsRowTone.destructive,
  onTap: _openDeleteDialog,
)

Row with leading icon:

MSSettingsRow(
  title: 'Notifications',
  icon: Icons.notifications_none_outlined,
  trailing: const MSSwitch(value: true, onChanged: null),
)