v2.2.1: frontend closed-source + Docker one-click deploy

- Remove frontend source code (now in private repo)
- Add pre-built frontend/dist/ with Nginx serving
- Simplify docker-compose.yml (no Node.js build needed)
- Update README with docs index and Docker deploy guide
- Add admin order list and AI analysis stats tabs
- Add quick trade API routes
- Clean up redundant files (package-lock.json, yarn.lock, .iml)
- Add GitHub Actions workflow for frontend update automation

quantdinger_vue/src/components/SettingDrawer/SettingItem.vue

@@ -1,38 +0,0 @@
-<template>
-  <div class="setting-drawer-index-item">
-    <h3 class="setting-drawer-index-title">{{ title }}</h3>
-    <slot></slot>
-    <a-divider v-if="divider"/>
-  </div>
-</template>
-
-<script>
-export default {
-  name: 'SettingItem',
-  props: {
-    title: {
-      type: String,
-      default: ''
-    },
-    divider: {
-      type: Boolean,
-      default: false
-    }
-  }
-}
-</script>
-
-<style lang="less" scoped>
-
-  .setting-drawer-index-item {
-    margin-bottom: 24px;
-
-    .setting-drawer-index-title {
-      font-size: 14px;
-      color: rgba(0, 0, 0, .85);
-      line-height: 22px;
-      margin-bottom: 12px;
-    }
-
-  }
-</style>