feat(#261): add tpsl params missing from position endpoints. add new endpoint for add/reduce margin. add doc examples

examples/apidoc/V5/Position/switch-cross-isolated-margin.js

@@ -0,0 +1,22 @@
+const { RestClientV5 } = require('bybit-api');
+
+const client = new RestClientV5({
+  testnet: true,
+  key: 'apikey',
+  secret: 'apisecret',
+});
+
+client
+  .switchIsolatedMargin({
+    category: 'linear',
+    symbol: 'ETHUSDT',
+    tradeMode: 1,
+    buyLeverage: '10',
+    sellLeverage: '10',
+  })
+  .then((response) => {
+    console.log(response);
+  })
+  .catch((error) => {
+    console.error(error);
+  });