feat(v2): remove old dashboard, add vitae + resizable windows

- Removed old Recharts dashboard view entirely (no more viewMode
  toggle, DashboardView lazy import, Ctrl+D shortcut)
- Recharts chunk eliminated from build — bundle size reduced
- Player Dashboard window: added Vitae column (red when > 0%)
- ALL windows now resizable: drag bottom-right corner handle
  (min 300×200px). Subtle diagonal line grip indicator.
- Sidebar: removed 📊 Dashboard toggle link, removed broken
  /quest-status.html external link (replaced by 📜 Quests window)

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

frontend/src/styles/map-layout.css

@@ -528,6 +528,18 @@
   flex-direction: column;
 }
 
+.ml-window-resize {
+  position: absolute;
+  bottom: 0;
+  right: 0;
+  width: 14px;
+  height: 14px;
+  cursor: nwse-resize;
+  opacity: 0.3;
+  background: linear-gradient(135deg, transparent 50%, #888 50%, transparent 52%, #888 65%, transparent 67%, #888 80%);
+}
+.ml-window-resize:hover { opacity: 0.6; }
+
 /* ── Stats window (Grafana iframes) ───────────────────── */
 .ml-stats-controls {
   display: flex;