Add admin panel web UI (Svelte 5)

Dashboard with launch stats, instance manager with Modrinth/CurseForge
search and zip import, player and group management, launcher design
editor with live preview, and sign-in settings.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011ARcGWxLx21FwXJ3yfGriS

panel/web/src/components/Toasts.svelte

@@ -0,0 +1,28 @@
+<script lang="ts">
+  import { CircleCheck, CircleAlert, Info, X } from '@lucide/svelte';
+  import { dismiss, toasts } from '../lib/toast.svelte';
+</script>
+
+<div class="toasts" aria-live="polite">
+  {#each toasts as t (t.id)}
+    <div class="toast {t.kind}">
+      {#if t.kind === 'ok'}<CircleCheck size={18} />{:else if t.kind === 'error'}<CircleAlert size={18} />{:else}<Info size={18} />{/if}
+      <span>{t.text}</span>
+      <button class="ghost icon" onclick={() => dismiss(t.id)} aria-label="Dismiss"><X size={14} /></button>
+    </div>
+  {/each}
+</div>
+
+<style>
+  .toasts { position: fixed; right: 20px; bottom: 20px; display: flex; flex-direction: column; gap: 10px; z-index: 100; max-width: 420px; }
+  .toast {
+    display: flex; align-items: center; gap: 10px; padding: 10px 10px 10px 14px; border-radius: 12px;
+    background: rgba(24, 27, 41, 0.92); backdrop-filter: blur(12px); border: 1px solid var(--line-strong);
+    box-shadow: var(--shadow); animation: pop 0.2s ease; font-size: 0.9rem;
+  }
+  .toast span { flex: 1; }
+  .ok :global(svg:first-child) { color: var(--good); }
+  .error :global(svg:first-child) { color: var(--bad); }
+  .info :global(svg:first-child) { color: var(--accent-2); }
+  @keyframes pop { from { opacity: 0; transform: translateY(8px) scale(0.98); } }
+</style>