Refactoring: port "statisticsGUI" to svelte

src/UI/Statistics/StatisticsGui.svelte

@@ -0,0 +1,30 @@
+<script lang="ts">
+  import { UIEventSource } from "../../Logic/UIEventSource"
+  import { Utils } from "../../Utils"
+  import Loading from "../Base/Loading.svelte"
+  import AllStats from "./AllStats.svelte"
+
+  let homeUrl =
+    "https://raw.githubusercontent.com/pietervdvn/MapComplete-data/main/changeset-metadata/"
+  let stats_files = "file-overview.json"
+
+  let indexFile = UIEventSource.FromPromise(
+    Utils.downloadJson<string[]>(homeUrl + stats_files)
+  )
+
+</script>
+
+<div class="m-4">
+  <div class="flex justify-between">
+
+    <h2>Statistics of changes made with MapComplete</h2>
+    <a href="/" class="button">Back to index</a>
+  </div>
+  {#if $indexFile === undefined}
+    <Loading>Loading index file...</Loading>
+  {:else}
+    <AllStats paths={$indexFile.filter(p => p.startsWith("stats")).map(p => homeUrl+"/"+p)} />
+  {/if}
+
+</div>
+