feat: add analysis pages and raster risk map

Ship a new app version with broader analytics, restructured
dashboards, and a server-rendered risk map.

Frontend:
- Add Overview, Demographic, Disease, and Environmental Health
  analysis pages
- Add AnomalyMarkers, CalendarHeatmap, and MetricHeatmapTable
  components
- Rebuild Alerts map onto server-rendered raster risk tiles;
  expand Monitoring, Trend, and District Comparison views
- Extend API client, stores, and TypeScript types

Backend:
- Add environment router (pollutants, lag correlations)
- Add risk_raster util serving XYZ 100m risk tiles
- Expand cases endpoints (demographics, seasonality, diagnoses)
  and insights; harden auth and file-based loaders

Data & tooling:
- Add processed outpatient/inpatient/combined case parquet (LFS)
- Add nested CLAUDE.md guides, pyrightconfig, and test updates

frontend/src/components/LodGridLayer.tsx

@@ -18,9 +18,9 @@ for (const [, , color] of RISK_COLORS) {
 
 function getRiskColor(value: number): string {
   for (const [min, max, color] of RISK_COLORS) {
-    if (value >= min && value <= max) return color;
+    if (value >= min && value < max) return color;
   }
-  return '#22c55e';
+  return '#ef4444';
 }
 
 // 100m grid step in degrees
@@ -116,6 +116,7 @@ export function LodGridLayer({
     canvas.style.width = '100%';
     canvas.style.height = '100%';
     canvas.style.pointerEvents = 'none';
+    canvas.style.display = visibleRef.current ? '' : 'none';
     pane.appendChild(canvas);
     canvasRef.current = canvas;
 
@@ -173,8 +174,8 @@ export function LodGridLayer({
         canvas.style.transform = '';
         drawnOriginRef.current = null;
 
-        if (!visibleRef.current) return;
-
+        // Visibility is controlled via canvas CSS display (see visible effect),
+        // so we still draw pixels even when hidden to keep them ready on re-show.
         const currentGrids = gridsRef.current;
         if (!currentGrids || currentGrids.length === 0) return;
 
@@ -354,13 +355,21 @@ export function LodGridLayer({
     };
   }, [map]);
 
-  // Trigger redraw when data changes
+  // Trigger redraw when data/geometry-affecting inputs change.
   useEffect(() => {
     const canvas = canvasRef.current;
     if (canvas && (canvas as any).__lodRedraw) {
       (canvas as any).__lodRedraw();
     }
-  }, [grids, forecastDay, riskRange, visible]);
+  }, [grids, forecastDay, riskRange]);
+
+  // Visibility toggle: hide/show via CSS instead of a full geometry redraw.
+  useEffect(() => {
+    const canvas = canvasRef.current;
+    if (canvas) {
+      canvas.style.display = visible ? '' : 'none';
+    }
+  }, [visible]);
 
   return null;
 }