feat: backend for warnings, partial frontend for reports

frontend/src/routes/reports/ReportCard.svelte

@@ -0,0 +1,24 @@
+<script lang="ts">
+  import type { Report } from "$lib/api/entities";
+  import { DateTime } from "luxon";
+  import { Button, Card, CardBody, CardFooter, CardHeader } from "sveltestrap";
+
+  export let report: Report;
+</script>
+
+<Card>
+  <CardHeader>
+    <strong>#{report.id}</strong> on <a href="/@{report.user_name}">@{report.user_name}</a>
+    ({report.user_id}) {#if report.member_id}
+      (member: <a href="/@{report.user_name}/{report.member_name}">{report.member_name}</a>,
+      {report.member_id})
+    {/if}
+  </CardHeader>
+  <CardBody>
+    <blockquote class="blockquote">{report.reason}</blockquote>
+  </CardBody>
+  <CardFooter>
+    Created {DateTime.fromISO(report.created_at).toLocal().toLocaleString(DateTime.DATETIME_MED)}
+    <slot />
+  </CardFooter>
+</Card>