linux: wayland: implement cursor style handling (#8632)

Release Notes:

- Implemented cursor style changing in wayland


[zed_cursor_wayland.webm](https://github.com/zed-industries/zed/assets/12579216/cbc03f85-41c1-4687-88b5-2aa5612d7129)

---------

Co-authored-by: Mikayla <mikayla@zed.dev>

crates/gpui/src/platform/linux/wayland/cursor.rs

@@ -0,0 +1,67 @@
+use crate::platform::linux::wayland::WaylandClientState;
+use wayland_backend::client::InvalidId;
+use wayland_client::protocol::wl_compositor::WlCompositor;
+use wayland_client::protocol::wl_pointer::WlPointer;
+use wayland_client::protocol::wl_shm::WlShm;
+use wayland_client::protocol::wl_surface::WlSurface;
+use wayland_client::{Connection, QueueHandle};
+use wayland_cursor::{CursorImageBuffer, CursorTheme};
+
+pub(crate) struct Cursor {
+    theme: Result<CursorTheme, InvalidId>,
+    current_icon_name: String,
+    surface: WlSurface,
+    serial_id: u32,
+}
+
+impl Cursor {
+    pub fn new(
+        connection: &Connection,
+        compositor: &WlCompositor,
+        qh: &QueueHandle<WaylandClientState>,
+        shm: &WlShm,
+        size: u32,
+    ) -> Self {
+        Self {
+            theme: CursorTheme::load(&connection, shm.clone(), size),
+            current_icon_name: "".to_string(),
+            surface: compositor.create_surface(qh, ()),
+            serial_id: 0,
+        }
+    }
+
+    pub fn set_serial_id(&mut self, serial_id: u32) {
+        self.serial_id = serial_id;
+    }
+
+    pub fn set_icon(&mut self, wl_pointer: &WlPointer, cursor_icon_name: String) {
+        if self.current_icon_name != cursor_icon_name {
+            if self.theme.is_ok() {
+                if let Some(cursor) = self.theme.as_mut().unwrap().get_cursor(&cursor_icon_name) {
+                    let buffer: &CursorImageBuffer = &cursor[0];
+                    let (width, height) = buffer.dimensions();
+                    let (hot_x, hot_y) = buffer.hotspot();
+
+                    wl_pointer.set_cursor(
+                        self.serial_id,
+                        Some(&self.surface),
+                        hot_x as i32,
+                        hot_y as i32,
+                    );
+                    self.surface.attach(Some(&buffer), 0, 0);
+                    self.surface.damage(0, 0, width as i32, height as i32);
+                    self.surface.commit();
+
+                    self.current_icon_name = cursor_icon_name;
+                } else {
+                    log::warn!(
+                        "Linux: Wayland: Unable to get cursor icon: {}",
+                        cursor_icon_name
+                    );
+                }
+            } else {
+                log::warn!("Linux: Wayland: Unable to load cursor themes");
+            }
+        }
+    }
+}