gpui: Add PathBuilder based on lyon to build Path (#22808)

Release Notes:

- N/A

---

Continue https://github.com/zed-industries/zed/pull/20499

We to draw more complex Path. Before this change, we only have
`line_to`, but it is not enough.

Add a new `PathBuilder` to use [lyon](https://github.com/nical/lyon) to
build more complex path.

And then with PR #22812 to enable anti-aliasing, all thing will be
perfect.
## Show case

```bash
cargo run -p gpui --example painting
```

Before:

<img width="1136" alt="image"
src="https://github.com/user-attachments/assets/0c15833a-ec95-404c-a469-24cf172cfd86"
/>

After:

<img width="1136" alt="image"
src="https://github.com/user-attachments/assets/42cfa35e-7e8f-4ef3-bb2d-b98defc62ad6"
/>

crates/gpui/src/gpui.rs

@@ -82,6 +82,7 @@ mod input;
 mod interactive;
 mod key_dispatch;
 mod keymap;
+mod path_builder;
 mod platform;
 pub mod prelude;
 mod scene;
@@ -135,6 +136,7 @@ pub use input::*;
 pub use interactive::*;
 use key_dispatch::*;
 pub use keymap::*;
+pub use path_builder::*;
 pub use platform::*;
 pub use refineable::*;
 pub use scene::*;