feat(maps): Phase 4 — city venue dot map

New serving model: city_venue_locations joins dim_venues + dim_cities
to expose lat/lon/court_count per venue for the city dot map endpoint.

pseo_city_costs_de.sql: add c.lat, c.lon so city-cost articles have
city coordinates for the #city-map data attributes.

city-cost-de.md.jinja: add #city-map div (both DE and EN sections)
after the stats strip. Leaflet init handled by article_detail.html.

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

transform/sqlmesh_padelnomics/models/serving/city_venue_locations.sql

@@ -0,0 +1,26 @@
+-- Per-venue lat/lon for the city detail dot map.
+-- Joins dim_venues to dim_cities to attach country_slug and city_slug
+-- (needed by the /api/markets/<country>/<city>/venues.json endpoint).
+-- Only rows with valid coordinates are included.
+
+MODEL (
+  name serving.city_venue_locations,
+  kind FULL,
+  cron '@daily',
+  grain venue_id
+);
+
+SELECT
+  v.venue_id,
+  v.name,
+  v.lat,
+  v.lon,
+  v.court_count,
+  v.indoor_court_count,
+  v.outdoor_court_count,
+  v.city_slug,
+  c.country_slug
+FROM foundation.dim_venues v
+JOIN foundation.dim_cities c
+  ON v.country_code = c.country_code AND v.city_slug = c.city_slug
+WHERE v.lat IS NOT NULL AND v.lon IS NOT NULL

transform/sqlmesh_padelnomics/models/serving/pseo_city_costs_de.sql

@@ -22,6 +22,9 @@ SELECT
   c.country_code,
   c.country_name_en,
   c.country_slug,
+  -- City coordinates (for the city venue dot map)
+  c.lat,
+  c.lon,
   -- Market metrics
   c.population,
   c.padel_venue_count,

web/src/padelnomics/content/templates/city-cost-de.md.jinja

@@ -39,6 +39,8 @@ priority_column: population
   </div>
 </div>
 
+<div id="city-map" data-country-slug="{{ country_slug }}" data-city-slug="{{ city_slug }}" data-lat="{{ lat }}" data-lon="{{ lon }}" style="height:300px; border-radius:12px; margin-bottom:1.5rem;"></div>
+
 {{ city_name }} erreicht einen **<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> von {{ market_score | round(1) }}/100** — damit liegt die Stadt{% if market_score >= 55 %} unter den stärksten Padel-Märkten in {{ country_name_en }}{% elif market_score >= 35 %} im soliden Mittelfeld der Padel-Märkte in {{ country_name_en }}{% else %} in einem frühen Padel-Markt mit Wachstumspotenzial{% endif %}. Aktuell gibt es **{{ padel_venue_count }} Padelanlagen** für {% if population >= 1000000 %}{{ (population / 1000000) | round(1) }}M{% else %}{{ (population / 1000) | round(0) | int }}K{% endif %} Einwohner — das entspricht {{ venues_per_100k | round(1) }} Anlagen pro 100.000 Einwohner.{% if opportunity_score %} Der **<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> Opportunity Score</a> von {{ opportunity_score | round(1) }}/100** bewertet das Investitionspotenzial — Versorgungslücken, Einzugsgebiet und Sportaffinität der Region:{% if opportunity_score >= 65 and market_score < 40 %} überschaubare Konkurrenz trifft auf starkes Standortpotenzial{% elif opportunity_score >= 65 %} hohes Potenzial trotz bereits aktivem Marktumfeld{% elif opportunity_score >= 40 %} solides Potenzial, der Markt beginnt sich zu verdichten{% else %} der Standort ist vergleichsweise gut versorgt, Differenzierung wird zum Schlüssel{% endif %}.{% endif %}
 
 Die entscheidende Frage für Investoren: Was bringt ein Padel-Investment bei den aktuellen Preisen, Auslastungsraten und Baukosten tatsächlich? Das Finanzmodell unten rechnet mit echten Marktdaten aus {{ city_name }}.
@@ -179,6 +181,8 @@ Der **Market Score ({{ market_score | round(1) }}/100)** misst die *Marktreife*:
   </div>
 </div>
 
+<div id="city-map" data-country-slug="{{ country_slug }}" data-city-slug="{{ city_slug }}" data-lat="{{ lat }}" data-lon="{{ lon }}" style="height:300px; border-radius:12px; margin-bottom:1.5rem;"></div>
+
 {{ city_name }} has a **<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> of {{ market_score | round(1) }}/100** — placing it{% if market_score >= 55 %} among the strongest padel markets in {{ country_name_en }}{% elif market_score >= 35 %} in the mid-tier of {{ country_name_en }}'s padel markets{% else %} in an early-stage padel market with room for growth{% endif %}. The city currently has **{{ padel_venue_count }} padel venues** serving a population of {% if population >= 1000000 %}{{ (population / 1000000) | round(1) }}M{% else %}{{ (population / 1000) | round(0) | int }}K{% endif %} residents — a density of {{ venues_per_100k | round(1) }} venues per 100,000 people.{% if opportunity_score %} The **<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> Opportunity Score</a> of {{ opportunity_score | round(1) }}/100** scores investment potential — supply gaps, catchment reach, and sports culture as a demand proxy:{% if opportunity_score >= 65 and market_score < 40 %} limited competition meets strong location fundamentals{% elif opportunity_score >= 65 %} strong potential despite an already active market{% elif opportunity_score >= 40 %} solid potential as the market starts to fill in{% else %} the area is comparatively well-served; differentiation is the key lever{% endif %}.{% endif %}
 
 The question that matters: given current pricing, occupancy, and build costs, what does a padel investment in {{ city_name }} actually return? The financial model below works with real local market data.