feat: 初始化项目结构与核心功能

引入项目基础目录结构，包含多语言支持、主要页面与组件、核心游戏逻辑、UI 组件库、加密与本地持久化、自动化 Docker 构建流程、GitHub issue 模板（中英文）、README（中英文）、LICENSE 及开发配置文件。实现 OGame 单机版主要功能模块，为后续开发和扩展奠定基础。

src/components/ui/select/SelectScrollDownButton.vue

@@ -0,0 +1,26 @@
+<template>
+  <SelectScrollDownButton
+    data-slot="select-scroll-down-button"
+    v-bind="forwardedProps"
+    :class="cn('flex cursor-default items-center justify-center py-1', props.class)"
+  >
+    <slot>
+      <ChevronDown class="size-4" />
+    </slot>
+  </SelectScrollDownButton>
+</template>
+
+<script setup lang="ts">
+  import type { SelectScrollDownButtonProps } from 'reka-ui'
+  import type { HTMLAttributes } from 'vue'
+  import { reactiveOmit } from '@vueuse/core'
+  import { ChevronDown } from 'lucide-vue-next'
+  import { SelectScrollDownButton, useForwardProps } from 'reka-ui'
+  import { cn } from '@/lib/utils'
+
+  const props = defineProps<SelectScrollDownButtonProps & { class?: HTMLAttributes['class'] }>()
+
+  const delegatedProps = reactiveOmit(props, 'class')
+
+  const forwardedProps = useForwardProps(delegatedProps)
+</script>