deps: react-leaflet 1.8 -> 4.2 (+ leaflet 1.9) — the last legacy react-* lib

Ground-up hooks rewrite of the app's core map. Removes the final batch of
React-19-blocking warnings (legacy context on Map/LayersControl/TileLayer/
Marker/CircleMarker/Circle/Tooltip + ReactDOM.render from the old controls).

Core: <Map> -> <MapContainer>; .leafletElement refs (6 files) -> the map/
layer instances directly, via a <MapReady> child (useMap) + plain refs on
Marker/Circle/GeoJSON; controlled viewport (onViewportChanged + state.center/
zoom) -> <MapEvents> (useMapEvents moveend/zoomend) + imperative setView;
onClick -> eventHandlers={{click}}; Path styling -> pathOptions/style;
subsUnion takes the L.Map directly.

The 4 v1-only plugins reimplemented (new in-repo helpers under Maps/):
- react-leaflet-control -> MapControl (L.Control + createPortal)
- react-leaflet-google  -> GoogleMutantLayer (createLayerComponent +
  leaflet.gridlayer.googlemutant; Google Maps API already loaded by Gkeys)
- react-leaflet-fullscreen -> createControlComponent + leaflet.fullscreen
- leaflet-sleep / leaflet-graphicscale kept as vanilla (work on leaflet 1.9)

Browser-verified: /fires (tiles, OSM+Google layer switch, custom control,
fullscreen, graphic scale, pan/zoom -> re-fetch, no NaN), fire detail
(GeoJSON rect + fitBounds), home (3 maps coexist; SelectionMap draggable
marker -> updatePosition + distance circle). Console now shows 0 React
warnings on home/fires. REST smoke byte-identical.

imports/ui/components/Maps/FireIconMark.js

@@ -33,9 +33,9 @@ class FireIconMark extends Component {
       lat, lon, scan, track, nasa, id, history, falsePositives, industries, neighbour, when, t
     } = this.props;
     return (
-      <div>
+      <Fragment>
         { !falsePositives && !industries &&
-          <Marker position={[lat, lon]} icon={nasa ? this.getIcon(scan) : nFireIcon} onClick={this.onClick} >
+          <Marker position={[lat, lon]} icon={nasa ? this.getIcon(scan) : nFireIcon} eventHandlers={{ click: this.onClick }} >
             <FirePopup t={t} history={history} id={id} nasa={nasa} lat={lat} lon={lon} when={when} />
           </Marker> }
         { industries && <Marker position={[lat, lon]} icon={regIndustryIcon}>
@@ -43,23 +43,20 @@ class FireIconMark extends Component {
                         </Marker> }
         { /* disabled */ industries && false && <CircleMarker
           center={[lat, lon]}
-          color="violet"
-          stroke={false}
-          fillOpacity="1"
-          fill
           radius={1}
+          pathOptions={{ color: 'violet', stroke: false, fillOpacity: 1, fill: true }}
         />}
         { falsePositives && !industries &&
-        <Marker position={[lat, lon]} icon={industryIcon} onClick={this.onClick}>
+        <Marker position={[lat, lon]} icon={industryIcon} eventHandlers={{ click: this.onClick }}>
           <Tooltip><Fragment>{t('Es una industria (fuente: nuestros usuarios/as)')}</Fragment></Tooltip>
           { /* disabled because was a past fire (and can be marked multiple times) */ false && <FirePopup t={t} history={history} id={id} lat={lat} lon={lon} /> }
         </Marker>
           }
         { !falsePositives && !industries &&
-        <CircleMarker center={[lat, lon]} color={nasa ? 'red' : '#D35400'} stroke={false} fillOpacity="1" fill radius={1} onClick={this.onClick}>
+        <CircleMarker center={[lat, lon]} radius={1} pathOptions={{ color: nasa ? 'red' : '#D35400', stroke: false, fillOpacity: 1, fill: true }} eventHandlers={{ click: this.onClick }}>
           <FirePopup t={t} history={history} id={id} nasa={nasa} lat={lat} lon={lon} when={when} />
         </CircleMarker> }
-      </div>
+      </Fragment>
     );
   }
 }