feat(v2): Quest Status + Player Dashboard as React windows

Quest Status window (📜 Quests in sidebar):
- Fetches GET /quest-status API (polls every 30s)
- Grid: characters as rows × all unique quests as columns
- "READY" shown in green, countdowns in yellow, missing as dash
- Quest names shortened (removes "Timer", "Pickup" suffixes)
- Sticky header row, scrollable body
- Replaces broken quest-status.html link

Player Dashboard window (👥 Dashboard in sidebar):
- Sortable table of all online characters
- Columns: Character, State, KPH, Session kills, Total kills,
  Rares (total + session), Deaths, Uptime, HP%, Tapers
- Click column headers to sort (ascending/descending toggle)
- State badges: green=combat/hunt, red=other, gray=idle
- KPH in green, rares in gold, deaths in red (if > 0)
- HP% color-coded: green >80%, yellow >40%, red below

Sidebar changes:
- Removed broken /quest-status.html external link
- Added 👥 Dashboard + 📜 Quests as window opener buttons
- Both lazy-loaded (only fetched when first opened)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/components/sidebar/SidebarWindowButtons.tsx

@@ -6,6 +6,10 @@ export const SidebarWindowButtons: React.FC = () => {
 
   return (
     <div className="ml-tool-links">
+      <span className="ml-tool-link" style={{ cursor: 'pointer' }}
+        onClick={() => openWindow('playerdash', 'Player Dashboard')}>👥 Dashboard</span>
+      <span className="ml-tool-link" style={{ cursor: 'pointer' }}
+        onClick={() => openWindow('queststatus', 'Quest Status')}>📜 Quests</span>
       <span className="ml-tool-link" style={{ cursor: 'pointer' }}
         onClick={() => openWindow('issues', 'Issues Board')}>📋 Issues</span>
       <span className="ml-tool-link" style={{ cursor: 'pointer' }}