Add Map Layer

Adds a new data layer to the existing map page. Supports heatmaps, clustered markers, polygon overlays, and isochrone areas.

Inputs to gather

• Layer type — heatmap, markers, clusters, polygons, isochrone
• Data source — API endpoint that returns GeoJSON or coordinate data
• Visual encoding — what property maps to color/size (e.g., price → heat intensity)
• Toggle — should the user be able to show/hide this layer?

Steps

1. Create the data API endpoint:

   router.get("/analytics/geo/{layer-name}", authenticateToken, async (req, res) => {
     const data = await prisma.properties.findMany({
       where: { latitude: { not: null } },
       select: { id: true, latitude: true, longitude: true, price: true, type: true },
     });
     // Return as GeoJSON FeatureCollection
     res.json({
       type: "FeatureCollection",
       features: data.map(p => ({
         type: "Feature",
         geometry: { type: "Point", coordinates: [p.longitude, p.latitude] },
         properties: { id: p.id, price: Number(p.price), type: p.type },
       })),
     });
   });