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/FullScreenMap.js

@@ -1,25 +1,27 @@
 /* eslint-disable react/jsx-indent-props */
 /* eslint-disable import/no-absolute-path */
-/* eslint-disable import/no-absolute-path */
 
-import React, { Component } from 'react';
+import React from 'react';
 import PropTypes from 'prop-types';
 import { withTranslation } from 'react-i18next';
-import FullscreenControl from 'react-leaflet-fullscreen';
-import 'react-leaflet-fullscreen/dist/styles.css';
+import { createControlComponent } from '@react-leaflet/core';
+import L from 'leaflet';
+import 'leaflet.fullscreen';
+import 'leaflet.fullscreen/Control.FullScreen.css';
 
-class FullScreenMap extends Component {
-  render() {
-    const { t } = this.props;
-    return (
-      <FullscreenControl
-          position="topleft"
-          title={t('Pantalla completa')}
-          titleCancel={t('Salir de pantalla completa')}
-      />
-    );
-  }
-}
+// Replacement for react-leaflet-fullscreen (v1-only): wrap the vanilla
+// leaflet.fullscreen control with react-leaflet v4's control factory.
+const FullscreenControl = createControlComponent(
+  ({ position = 'topleft', title, titleCancel }) => L.control.fullscreen({ position, title, titleCancel })
+);
+
+const FullScreenMap = ({ t }) => (
+  <FullscreenControl
+      position="topleft"
+      title={t('Pantalla completa')}
+      titleCancel={t('Salir de pantalla completa')}
+  />
+);
 
 FullScreenMap.propTypes = {
   t: PropTypes.func.isRequired