接入自建后端 + Gitea CI/CD

- 新增 server/：Node + Express + SQLite + node-cron 实现登录、纪念日 CRUD 和定时订阅消息推送
- 新增 .gitea/workflows/deploy.yml：推送即触发群晖 Docker 部署，监听 15002
- utils/api.js：自动按 envVersion 切换本地/线上 BASE_URL
- app.js 与 add-anniversary.js 移除 wx.cloud 调用，改走自建后端
- cloudfunctions/ 暂保留以便回滚
- 一并提交此前未入库的首页 / 设置页 / 日历 / 万年历等改造

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

server/src/db.js

@@ -0,0 +1,51 @@
+const Database = require('better-sqlite3')
+const path = require('path')
+const fs = require('fs')
+
+const dbPath = process.env.DB_PATH || path.join(__dirname, '..', 'data', 'birthday.db')
+
+// 确保数据目录存在
+const dir = path.dirname(dbPath)
+if (!fs.existsSync(dir)) fs.mkdirSync(dir, { recursive: true })
+
+const db = new Database(dbPath)
+db.pragma('journal_mode = WAL')
+
+// 纪念日表：兼容原云数据库 anniversaries 集合字段
+db.exec(`
+  CREATE TABLE IF NOT EXISTS anniversaries (
+    id              TEXT PRIMARY KEY,
+    openid          TEXT NOT NULL,
+    personId        TEXT,
+    personName      TEXT,
+    type            TEXT,
+    customTypeName  TEXT,
+    isLunar         INTEGER DEFAULT 0,
+    solarYear       INTEGER,
+    solarMonth      INTEGER,
+    solarDay        INTEGER,
+    importance      TEXT,
+    remindEnabled   INTEGER DEFAULT 0,
+    remindDays      INTEGER DEFAULT 0,
+    remark          TEXT,
+    createTime      INTEGER,
+    updateTime      INTEGER
+  );
+  CREATE INDEX IF NOT EXISTS idx_anniv_openid ON anniversaries(openid);
+  CREATE INDEX IF NOT EXISTS idx_anniv_remind ON anniversaries(remindEnabled);
+
+  CREATE TABLE IF NOT EXISTS remind_logs (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    anniversaryId   TEXT,
+    personName      TEXT,
+    typeName        TEXT,
+    daysUntil       INTEGER,
+    sendDate        INTEGER,
+    status          TEXT,
+    error           TEXT
+  );
+  CREATE INDEX IF NOT EXISTS idx_log_anniv ON remind_logs(anniversaryId);
+  CREATE INDEX IF NOT EXISTS idx_log_date ON remind_logs(sendDate);
+`)
+
+module.exports = db