fix: handle invalid weather API key gracefully and fix TideDisplay crash

- Fix TideDisplay component crash (use extremes instead of tides)
- Handle 401 weather API errors gracefully (return null data with note)
- Update weather controller to return 200 with null values instead of 503
- Add helpful message about API key activation time
- Fix tide type capitalization (High/Low instead of high/low)

server/src/services/externalDataService.ts

@@ -150,8 +150,13 @@ export const getWeatherData = async (
     cache.set(cacheKey, weatherData, CACHE_EXPIRATION);
 
     return weatherData;
-  } catch (error) {
-    console.error('Error fetching weather data:', error);
+  } catch (error: any) {
+    // Handle specific error cases
+    if (error.response?.status === 401) {
+      console.warn('OpenWeatherMap API key is invalid or not activated yet. Keys can take a few hours to activate.');
+    } else {
+      console.error('Error fetching weather data:', error.message);
+    }
     return null;
   }
 };