feat(ui): add InputColor and custom theme

packages/ui/src/routes/ThemeSelector.svelte

@@ -0,0 +1,27 @@
+<script lang="ts">
+  import { InputSelect } from '$lib';
+  const themes = [
+    'dark',
+    'light',
+    'solarized',
+    'catppuccin',
+    'high-contrast',
+    'nord',
+    'dracula',
+    'custom'
+  ];
+
+  let { theme = $bindable() } = $props();
+
+  let themeIndex = $state(0);
+  $effect(() => {
+    theme = themes[themeIndex];
+    const classList = document.documentElement.classList;
+    for (const c of classList) {
+      if (c.startsWith('theme-')) document.documentElement.classList.remove(c);
+    }
+    document.documentElement.classList.add(`theme-${themes[themeIndex]}`);
+  });
+</script>
+
+<InputSelect bind:value={themeIndex} options={themes}></InputSelect>