Rename CpuTab to a more general Engine

And make the CPU load visible

src/lib/CpuTab.svelte

@@ -1,4 +1,8 @@
-<h1 class="text-lg font-bold">CPU</h1>
+<script>
+	import { cpuPercentage } from './activities.js'
+</script>
+<h1 class="text-lg font-bold">Engine</h1>
+<p>CPU Load: <span class="font-bold">{$cpuPercentage}%</span></p>
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 <p>CheerpX can run securely run unmodified x86 binaries and libraries in the browser</p>
 <p>For more information: <a class="text-gray-300" href="https://cheerpx.io/" target="_blank">https://cheerpx.io</a></p>

src/lib/activities.js

@@ -2,3 +2,4 @@ import { writable } from 'svelte/store';
 
 export const cpuActivity = writable(false);
 export const diskActivity = writable(false);
+export const cpuPercentage = writable(0);