fix(mobile): full-screen member profile + permissions row wrap (M4)

Mobile-audit batch 4. Desktop paths unchanged (verified by two review passes).

- UserRoomProfileRenderer: the member/room profile was always an anchored,
  fixed-width (340px), non-scrolling PopOut, so on a phone the moderation
  actions / device list / notes fell off the bottom, unreachable. On
  ScreenSize.Mobile it now renders a full-screen, internally-scrollable Modal
  with an explicit Close button (the full-screen sheet covers the backdrop and
  the profile has no self-close, so a tap-to-dismiss / X is required); desktop
  keeps the exact same anchored PopOut. Uses the provider-free useScreenSize().
- PowersEditor: the Color/Name/Power row wraps on narrow widths (wrap="Wrap")
  instead of squishing the name field; inert at desktop widths.

The mobile close button addresses a dismissal-trap both reviewers flagged.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/features/common-settings/permissions/PowersEditor.tsx

@@ -119,7 +119,7 @@ function EditPower({ maxPower, power, tag, onSave, onClose }: EditPowerProps) {
   return (
     <Box onSubmit={handleSubmit} as="form" direction="Column" gap="400">
       <Box direction="Column" gap="300">
-        <Box gap="200">
+        <Box gap="200" wrap="Wrap">
           <Box shrink="No" direction="Column" gap="100">
             <Text size="L400">Color</Text>
             <Box gap="200">