Fix Chart.js loading issue in weather charts

- Added check for Chart.js availability before rendering
- Updated chart hooks to wait for Chart.js to load completely
- Prevents 'window.Chart is not a constructor' errors

🤖 Generated with [Claude Code](https://claude.ai/code)

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

assets/js/app.js

@@ -189,11 +189,26 @@ Object.keys(WeatherChartHooks).forEach(hookName => {
   Hooks[hookName] = {
     ...originalHook,
     mounted() {
-      if (window.VendorLoader) {
+      const self = this;
+      if (window.VendorLoader && !window.chartBundleLoaded) {
+        // Load chart bundle and wait for it to complete
         window.VendorLoader.loadCharts();
-      }
-      if (originalHook.mounted) {
-        originalHook.mounted.call(this);
+        // Wait a bit for charts to load, then call mounted
+        const checkChartLoaded = () => {
+          if (window.Chart) {
+            if (originalHook.mounted) {
+              originalHook.mounted.call(self);
+            }
+          } else {
+            setTimeout(checkChartLoaded, 50);
+          }
+        };
+        setTimeout(checkChartLoaded, 100);
+      } else {
+        // Chart bundle already loaded or loading, call mounted
+        if (originalHook.mounted) {
+          originalHook.mounted.call(this);
+        }
       }
     }
   };

assets/js/features/weather_charts.ts

@@ -1,5 +1,5 @@
 // Chart.js and date adapter are loaded globally from vendor bundle
-const Chart = window.Chart;
+// We'll access it later when it's actually loaded
 
 import type { ChartConfiguration, ChartType } from 'chart.js';
 import type { WeatherChartDataset, YAxisOptions } from '../types/chart-types';
@@ -301,6 +301,13 @@ function createChartHook(configKey: string): Hook {
                     }
                 };
                 
+                // Check if Chart.js is loaded
+                if (!window.Chart) {
+                    console.warn('Chart.js not loaded yet, retrying...');
+                    setTimeout(() => self.renderChart(), 100);
+                    return;
+                }
+                
                 self.chart = new window.Chart(canvas, chartConfig);
             };