feat: optimize KV storage read/write operations

- the state is now stored in a single KV key
- there is one write for cron and one read for render

src/components/monitorStatusHeader.js

@@ -1,17 +1,15 @@
 import config from '../../config.yaml'
 
-export default function MonitorStatusHeader({ operational, lastUpdate }) {
+export default function MonitorStatusHeader({kvMonitorsMetadata}) {
   let backgroundColor = 'green'
   let headerText = config.settings.allmonitorsOperational
   let textColor = 'black'
 
-  if (!operational) {
+  if (!kvMonitorsMetadata.monitorsOperational) {
     backgroundColor = 'yellow'
     headerText = config.settings.notAllmonitorsOperational
   }
 
-  const lastCheckAgo = Math.round((Date.now() - lastUpdate.value) / 1000)
-
   return (
     <div className={`ui inverted segment ${backgroundColor}`}>
       <div className="horizontal flex between">
@@ -19,9 +17,9 @@ export default function MonitorStatusHeader({ operational, lastUpdate }) {
           {headerText}
         </div>
         {
-          lastUpdate.metadata && typeof window !== 'undefined' && (
+          kvMonitorsMetadata.lastUpdate && typeof window !== 'undefined' && (
           <div className={`${textColor}-text`}>
-            checked {lastCheckAgo} sec ago (from {lastUpdate.metadata.loc})
+            checked {Math.round((Date.now() - kvMonitorsMetadata.lastUpdate.time) / 1000)} sec ago (from {kvMonitorsMetadata.lastUpdate.loc})
           </div>
           )
         }