feat: add global styles and transitions for dark mode support

- Created style.css for base styles and color variables for light and dark themes.
- Added tailwind.css for Tailwind CSS integration and custom theme variables.
- Introduced transitions.css to manage global transitions and reduce motion preferences.
- Updated tsconfig.app.json to include path aliases for easier imports.
- Modified tsconfig.json to set baseUrl and paths for module resolution.
- Added typed-router.d.ts for auto-generated route types.
- Enhanced vite.config.ts with Vue Router plugin, Tailwind CSS integration, and server proxy settings.

frontend/src/components/ui/dropdown-menu/DropdownMenuGroup.vue

@@ -0,0 +1,11 @@
+<script setup lang="ts">
+  import { DropdownMenuGroup, type DropdownMenuGroupProps } from "reka-ui";
+
+  const props = defineProps<DropdownMenuGroupProps>();
+</script>
+
+<template>
+  <DropdownMenuGroup data-slot="dropdown-menu-group" v-bind="props">
+    <slot />
+  </DropdownMenuGroup>
+</template>