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/postgres/01_demo.sql

@@ -0,0 +1,32 @@
+CREATE TABLE IF NOT EXISTS users (
+  id SERIAL PRIMARY KEY,
+  name VARCHAR(64) NOT NULL,
+  email VARCHAR(128),
+  status SMALLINT NOT NULL DEFAULT 1,
+  created_at TIMESTAMPTZ DEFAULT NOW()
+);
+CREATE TABLE IF NOT EXISTS orders (
+  id SERIAL PRIMARY KEY,
+  user_id INT NOT NULL,
+  amount NUMERIC(12,2) NOT NULL DEFAULT 0,
+  status VARCHAR(16) NOT NULL DEFAULT 'pending',
+  created_at TIMESTAMPTZ DEFAULT NOW()
+);
+CREATE TABLE IF NOT EXISTS order_items (
+  id SERIAL PRIMARY KEY,
+  order_id INT NOT NULL,
+  sku VARCHAR(64) NOT NULL,
+  qty INT NOT NULL DEFAULT 1,
+  price NUMERIC(12,2) NOT NULL DEFAULT 0
+);
+TRUNCATE order_items, orders, users RESTART IDENTITY;
+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);