added subprox

server/fastapi_app.py

@@ -344,6 +344,18 @@ def elevation_nearest_hill(
     return find_nearest_hill(lat, lon, radius_m, step_m, min_prominence_m)
 
 
+@app.get("/api/elevation/grid")
+def elevation_grid(
+    lat: float = Query(..., ge=-90.0, le=90.0),
+    lon: float = Query(..., ge=-180.0, le=180.0),
+    radius_m: float = Query(200.0, ge=100.0, le=500.0),
+    step_m: float = Query(0.0, ge=0.0, le=100.0),
+):
+    from core.elevation import build_elevation_grid
+
+    return build_elevation_grid(lat, lon, radius_m, step_m)
+
+
 @app.get("/api/health")
 def health():
     from core.elevation import elevation_status