feat: map overhaul, kiosk mode, RR importer, duplicate system

Map (MapView.tsx):
- Fan/hand-of-cards marker clustering: groups nearby markers by pixel
  proximity (union-find), renders as rotated color cards showing all types
- Pulsing ring CSS animation on recording nodes (pulse-ring keyframe)
- Live incident overlay panel — right sidebar (desktop) / bottom drawer (mobile),
  clickable to flyTo incident location
- Auto-fit button (⤢) fits all markers in view with fitBounds
- "Live · Xs ago" timestamp badge (refreshes every 10s)
- Weather Radar layer (NEXRAD via Iowa Env Mesonet, no API key)
- ADS-B + Meshtastic placeholder layers (off by default)

Map page (map/page.tsx):
- Fullscreen / kiosk toggle: fixed z-50 overlay covers nav, map fills viewport
- lastUpdated tracking passed to MapView for Live timestamp

Systems page (systems/page.tsx):
- Duplicate System button: opens form pre-filled with Copy of <name>
- RadioReference HTML import: file upload → DOMParser validates .rrlblue
  structure, parses talkgroup categories, modal lets user select which
  categories to import, auto-maps RR tags to local tags (law→police, etc.)

drb-frontend/app/globals.css

@@ -96,6 +96,15 @@ html:not(.dark) .text-indigo-300   { color: #4338ca !important; }
 html:not(.dark) .text-indigo-400   { color: #6366f1 !important; }
 html:not(.dark) .border-indigo-800 { border-color: #a5b4fc !important; }
 
+/* ── Pulsing ring for recording nodes ────────────────────────────────────── */
+@keyframes pulse-ring {
+  0%   { transform: scale(1);   opacity: 0.85; }
+  100% { transform: scale(2.4); opacity: 0;    }
+}
+.node-pulse-ring {
+  animation: pulse-ring 1.8s ease-out infinite;
+}
+
 /* ── Form inputs ─────────────────────────────────────────────────────────── */
 html:not(.dark) input:not([type="submit"]):not([type="button"]):not([type="reset"]),
 html:not(.dark) select,