feat(text): add raw! and styled! macros

These macros are similar to the format! macro, but return a raw or
styled Span instead of a String.

```rust
use ratatui_macros::{raw, styled};

let name = "world";
raw!("Hello, {name}!");
styled!(Style::new().green(), "Hello, {name}!");
styled!(Color::Green, "Hello, {name}!");
styled!(Modifier::BOLD, "Hello, {name}!");
```