feat(maps): Phase 3 — country overview city bubble map + article_detail Leaflet loader

Add #country-map div to country-overview.md.jinja (both DE/EN).
article_detail.html: always include Leaflet CSS, conditionally load
Leaflet JS only when #country-map or #city-map divs are present.
Initializes country city-bubble map and city venue-dot map from
/api/markets/{slug}/cities.json and /api/markets/{country}/{city}/venues.json.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/padelnomics/content/templates/article_detail.html

@@ -31,6 +31,7 @@
 }
 </script>
 {% endif %}
+<link rel="stylesheet" href="{{ url_for('static', filename='vendor/leaflet/leaflet.min.css') }}">
 {% endblock %}
 
 {% block content %}
@@ -57,3 +58,91 @@
   </article>
 </main>
 {% endblock %}
+
+{% block scripts %}
+<script>
+(function() {
+  var countryMapEl = document.getElementById('country-map');
+  var cityMapEl = document.getElementById('city-map');
+  if (!countryMapEl && !cityMapEl) return;
+
+  function scoreColor(score) {
+    if (score >= 60) return '#16A34A';
+    if (score >= 30) return '#D97706';
+    return '#DC2626';
+  }
+
+  function initCountryMap(el) {
+    var slug = el.dataset.countrySlug;
+    var map = L.map(el, {scrollWheelZoom: false});
+    L.tileLayer('https://{s}.basemaps.cartocdn.com/light_all/{z}/{x}/{y}{r}.png', {
+      attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OSM</a> &copy; <a href="https://carto.com/">CARTO</a>',
+      maxZoom: 18
+    }).addTo(map);
+    var lang = document.documentElement.lang || 'en';
+    fetch('/api/markets/' + slug + '/cities.json')
+      .then(function(r) { return r.json(); })
+      .then(function(data) {
+        if (!data.length) return;
+        var maxV = Math.max.apply(null, data.map(function(d) { return d.padel_venue_count || 1; }));
+        var bounds = [];
+        data.forEach(function(c) {
+          if (!c.lat || !c.lon) return;
+          var radius = 5 + 18 * Math.sqrt((c.padel_venue_count || 1) / maxV);
+          var color = scoreColor(c.market_score);
+          var marker = L.circleMarker([c.lat, c.lon], {
+            radius: radius,
+            fillColor: color, color: color,
+            fillOpacity: 0.6, opacity: 0.9, weight: 1
+          })
+          .bindTooltip(c.city_name + '<br>' + (c.padel_venue_count || 0) + ' venues', {className: 'map-tooltip'})
+          .on('click', function() { window.location = '/' + lang + '/markets/' + slug + '/' + c.city_slug; })
+          .addTo(map);
+          bounds.push([c.lat, c.lon]);
+        });
+        if (bounds.length) map.fitBounds(bounds, {padding: [20, 20]});
+      });
+  }
+
+  function initCityMap(el) {
+    var countrySlug = el.dataset.countrySlug;
+    var citySlug = el.dataset.citySlug;
+    var lat = parseFloat(el.dataset.lat);
+    var lon = parseFloat(el.dataset.lon);
+    var map = L.map(el, {scrollWheelZoom: false}).setView([lat, lon], 13);
+    L.tileLayer('https://{s}.basemaps.cartocdn.com/light_all/{z}/{x}/{y}{r}.png', {
+      attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OSM</a> &copy; <a href="https://carto.com/">CARTO</a>',
+      maxZoom: 18
+    }).addTo(map);
+    fetch('/api/markets/' + countrySlug + '/' + citySlug + '/venues.json')
+      .then(function(r) { return r.json(); })
+      .then(function(data) {
+        data.forEach(function(v) {
+          if (!v.lat || !v.lon) return;
+          var indoor = v.indoor_court_count || 0;
+          var outdoor = v.outdoor_court_count || 0;
+          var total = v.court_count || (indoor + outdoor);
+          var tip = v.name + (total ? '<br>' + total + ' courts' +
+            (indoor ? ' (' + indoor + ' indoor' : '') +
+            (outdoor ? (indoor ? ', ' : ' (') + outdoor + ' outdoor)' : (indoor ? ')' : '')) : '');
+          L.circleMarker([v.lat, v.lon], {
+            radius: 6,
+            fillColor: '#1D4ED8', color: '#1D4ED8',
+            fillOpacity: 0.6, opacity: 0.9, weight: 1
+          })
+          .bindTooltip(tip, {className: 'map-tooltip'})
+          .addTo(map);
+        });
+      });
+  }
+
+  var script = document.createElement('script');
+  script.src = '{{ url_for("static", filename="vendor/leaflet/leaflet.min.js") }}';
+  script.onload = function() {
+    if (countryMapEl) initCountryMap(countryMapEl);
+    if (cityMapEl) initCityMap(cityMapEl);
+  };
+  document.head.appendChild(script);
+})();
+</script>
+{% endblock %}

web/src/padelnomics/content/templates/country-overview.md.jinja

@@ -40,6 +40,8 @@ priority_column: total_venues
   </div>
 </div>
 
+<div id="country-map" data-country-slug="{{ country_slug }}" style="height:360px; border-radius:12px; margin-bottom:1.5rem;"></div>
+
 In {{ country_name_en }} erfassen wir aktuell **{{ total_venues }} Padelanlagen** in **{{ city_count }} Städten**. Der durchschnittliche <a href="/{{ language }}/market-score" style="text-decoration:none"><span style="font-family:'Bricolage Grotesque',sans-serif;font-weight:800;color:#0F172A;letter-spacing:-0.02em">padelnomics</span> Market Score</a> liegt bei **{{ avg_market_score }}/100**{% if avg_market_score >= 55 %} — ein starker Markt mit breiter Infrastruktur und belastbaren Preisdaten{% elif avg_market_score >= 35 %} — ein wachsender Markt mit guter Abdeckung{% else %} — ein aufstrebender Markt, in dem Früheinsteiger noch Premiumstandorte sichern können{% endif %}.
 
 ## Marktlandschaft
@@ -172,6 +174,8 @@ Der **Market Score (Ø {{ avg_market_score }}/100)** bewertet die Marktreife: Be
   </div>
 </div>
 
+<div id="country-map" data-country-slug="{{ country_slug }}" style="height:360px; border-radius:12px; margin-bottom:1.5rem;"></div>
+
 {{ country_name_en }} has **{{ total_venues }} padel venues** tracked across **{{ city_count }} cities**. The average <a href="/{{ language }}/market-score" style="text-decoration:none"><span style="font-family:'Bricolage Grotesque',sans-serif;font-weight:800;color:#0F172A;letter-spacing:-0.02em">padelnomics</span> Market Score</a> across tracked cities is **{{ avg_market_score }}/100**{% if avg_market_score >= 55 %} — a strong market with widespread venue penetration and solid pricing data{% elif avg_market_score >= 35 %} — a growing market with healthy city coverage{% else %} — an emerging market where early entrants can still capture prime locations{% endif %}.
 
 ## Market Landscape