Integrate chat panel into GuestKiosk

## Task Integrate the `SessionChatPanel` component into the guest's `GuestKiosk` interface. ## Layout Changes Add collapsible chat panel to guest UI: ``` ┌─────────────────────────────────────────┬──────────────┐ │ │ │ │ Operator Video │ Chat │ │ │ Panel │ │ │ (collapse) │ │ [Self PiP] │ │ ├─────────────────────────────────────────┴──────────────┤ │ Session info / footer [Chat] [Mic Check] │ └────────────────────────────────────────────────────────┘ ``` ## Integration Points 1. Add chat toggle button (with unread badge) to footer 2. Pass guest token to `SessionChatPanel` for ActionCable auth 3. Prompt for guest name on first message (or use "Guest") 4. Use ActionCable for real-time subscription 5. Handle session ended state gracefully ## Props to Pass ```jsx <SessionChatPanel sessionId={sessionId} participantType="guest" participantName={guestName || 'Guest'} token={guestToken} initialMessages={messages} isCollapsed={chatCollapsed} onToggle={() => setChatCollapsed(!chatCollapsed)} disabled={sessionState === 'ended'} /> ``` ## Guest Name Handling - Store in localStorage for session persistence - Optional: prompt modal on first message - Default to translated "Guest" if not provided ## Translations Add to `app/javascript/i18n/guest/translations.js`: - `guest.chat.title` - `guest.chat.placeholder` - `guest.chat.send` - `guest.chat.empty` - `guest.chat.name_prompt` ## Files to Modify - `app/javascript/components/remote_support/GuestKiosk.jsx` - `app/javascript/i18n/guest/translations.js` - `app/views/remote_support_guest/show.html.haml` (pass initial messages if needed) - `app/controllers/remote_support_guest_controller.rb` (include messages in response)