Initial commit: RSS platform phase 1 skeleton with code review fixes

Features:
- FastAPI + SQLAlchemy 2.0 async + PostgreSQL/pgvector + Redis backend
- Vue 3 + TypeScript + Element Plus frontend
- JWT auth with access/refresh tokens and revocation
- Admin/member RBAC
- RSS feed CRUD and article listing
- Settings management with Fernet encryption for sensitive values
- Redis distributed lock service
- Alembic initial migration
- Docker Compose development environment

Fixes from code review:
- Fix DB session leak in dependency injection
- Restrict registration to admin only
- Add default admin password warning
- Implement JWT refresh tokens and jti blacklist
- Strengthen password policy
- Use func.count for pagination totals
- Replace NullPool with AsyncAdaptedQueuePool
- Remove init_db from lifespan to enforce alembic migrations
- Add request_id middleware and logging filter
- Fix vite.config.ts env loading
- Add frontend token refresh interceptor
- Add Vue error handler

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/components/Layout.vue

@@ -0,0 +1,112 @@
+<template>
+  <el-container class="layout-container">
+    <el-aside width="220px" class="sidebar">
+      <div class="logo">
+        <el-icon size="28"><DataAnalysis /></el-icon>
+        <span>RSS Platform</span>
+      </div>
+      <el-menu
+        :default-active="$route.path"
+        router
+        class="sidebar-menu"
+        background-color="#1a1a2e"
+        text-color="#e2e8f0"
+        active-text-color="#409eff"
+      >
+        <el-menu-item index="/dashboard">
+          <el-icon><Odometer /></el-icon>
+          <span>仪表盘</span>
+        </el-menu-item>
+        <el-menu-item index="/feeds">
+          <el-icon><Connection /></el-icon>
+          <span>RSS 源</span>
+        </el-menu-item>
+        <el-menu-item index="/articles">
+          <el-icon><Document /></el-icon>
+          <span>文章</span>
+        </el-menu-item>
+      </el-menu>
+    </el-aside>
+
+    <el-container>
+      <el-header class="header">
+        <div class="header-right">
+          <span class="username">{{ authStore.user?.username }}</span>
+          <el-tag :type="authStore.isAdmin ? 'danger' : 'info'" size="small">
+            {{ authStore.isAdmin ? '管理员' : '成员' }}
+          </el-tag>
+          <el-button type="danger" size="small" @click="handleLogout">退出</el-button>
+        </div>
+      </el-header>
+
+      <el-main class="main-content">
+        <router-view />
+      </el-main>
+    </el-container>
+  </el-container>
+</template>
+
+<script setup lang="ts">
+import { useRoute, useRouter } from 'vue-router'
+import { useAuthStore } from '@/stores/auth'
+import { ElMessage } from 'element-plus'
+
+const route = useRoute()
+const router = useRouter()
+const authStore = useAuthStore()
+
+const handleLogout = () => {
+  authStore.logout()
+  ElMessage.success('已退出登录')
+  router.push('/login')
+}
+</script>
+
+<style scoped>
+.layout-container {
+  height: 100vh;
+}
+
+.sidebar {
+  background-color: #1a1a2e;
+  color: #e2e8f0;
+}
+
+.logo {
+  height: 60px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  gap: 10px;
+  font-size: 18px;
+  font-weight: bold;
+  border-bottom: 1px solid #2d3748;
+}
+
+.sidebar-menu {
+  border-right: none;
+}
+
+.header {
+  background-color: #ffffff;
+  border-bottom: 1px solid #e4e7ed;
+  display: flex;
+  align-items: center;
+  justify-content: flex-end;
+}
+
+.header-right {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+}
+
+.username {
+  font-weight: 500;
+}
+
+.main-content {
+  background-color: #f5f7fa;
+  padding: 20px;
+}
+</style>