feat: OpsxDB 桌面数据库客户端首版入库

含工作台/连库多引擎字段与 SSH·SSL、结果编辑、Redis 键浏览、
Tauri 桌面与 docs/落地页；排除本地构建产物与 sidecar 二进制。

tests/init/sqlite/01_demo.sql

@@ -0,0 +1,31 @@
+DROP TABLE IF EXISTS order_items;
+DROP TABLE IF EXISTS orders;
+DROP TABLE IF EXISTS users;
+CREATE TABLE users (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  name TEXT NOT NULL,
+  email TEXT,
+  status INTEGER NOT NULL DEFAULT 1,
+  created_at TEXT DEFAULT CURRENT_TIMESTAMP
+);
+CREATE TABLE orders (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  user_id INTEGER NOT NULL,
+  amount REAL NOT NULL DEFAULT 0,
+  status TEXT NOT NULL DEFAULT 'pending',
+  created_at TEXT DEFAULT CURRENT_TIMESTAMP
+);
+CREATE TABLE order_items (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  order_id INTEGER NOT NULL,
+  sku TEXT NOT NULL,
+  qty INTEGER NOT NULL DEFAULT 1,
+  price REAL NOT NULL DEFAULT 0
+);
+INSERT INTO users (name, email, status) VALUES
+  ('alice','alice@demo.local',1),('bob','bob@demo.local',1),('carol','carol@demo.local',1),
+  ('dave','dave@demo.local',0),('erin','erin@demo.local',1);
+INSERT INTO orders (user_id, amount, status) VALUES
+  (1,99.50,'paid'),(1,12.00,'pending'),(2,250.00,'paid'),(3,8.80,'cancelled'),(5,41.20,'paid');
+INSERT INTO order_items (order_id, sku, qty, price) VALUES
+  (1,'SKU-A',1,99.50),(2,'SKU-B',2,6.00),(3,'SKU-C',5,50.00),(4,'SKU-D',1,8.80),(5,'SKU-E',2,20.60);