Part 5 of the cloud UX overhaul. Cloud strategies and shared items
were visually identical to local ones, and a user's share role was
never surfaced.

- Add a shared CloudRoleBadge (lib/widgets/role_badge.dart): a muted
  cloud glyph pill for owned cloud strategies, a violet-tinted EDIT
  badge for editor shares, and a muted VIEW badge for viewer shares.
- Render the badge on cloud strategy tiles next to the name/metadata
  so it stays clear of the map thumbnail. Local tiles are unchanged.
- Show a non-interactive "View only" chip in the editor top strip when
  the open strategy is a cloud viewer share, with a tooltip pointing
  the user to the owner for edit access.

All colors come from Settings.tacticalVioletTheme tokens.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>