feat: UniswapX encoding example

examples/uniswapx-encoding-example/README.md

@@ -0,0 +1,12 @@
+# UniswapX Encoding Example
+
+This guide enables you to:
+
+1. Create a Solution object
+2. Create callback data for executing a UniswapX Order
+
+## How to run
+
+```bash
+cargo run --release --example uniswapx-encoding-example
+```