docs: add wcwidth to readme

README.md

@@ -32,6 +32,7 @@ Currently the following packages are available:
 - [`teatest`](./exp/teatest): a library for testing [Bubble Tea](https://github.com/charmbracelet/bubbletea) programs • [Docs](https://pkg.go.dev/github.com/charmbracelet/x/exp/teatest)
 - [`term`](./term): terminal utilities and helpers • [Docs](https://pkg.go.dev/github.com/charmbracelet/x/term)
 - [`termios`](./termios): Termios unified API and library • [Docs](https://pkg.go.dev/github.com/charmbracelet/x/termios)
+- [`wcwidth`](./wcwidth): Wide character width calculation • [Docs](https://pkg.go.dev/github.com/charmbracelet/x/wcwidth)
 - [`windows`](./windows): Windows API used at Charmbracelet • [Docs](https://pkg.go.dev/github.com/charmbracelet/x/windows)
 - [`xpty`](./xpty): cross-platform PTY interface • [Docs](https://pkg.go.dev/github.com/charmbracelet/x/xpty)