refactor: 迁移 shader.wgsl 至 static/wgsl/，新增 model 模块

src/model.rs

@@ -0,0 +1,15 @@
+use eframe::{
+    egui,
+    egui_wgpu::{self, wgpu},
+    wgpu::util::DeviceExt,
+};
+
+pub trait Vertex {
+    fn desc<'a>() -> wgpu::VertexBufferLayout<'a>;
+}
+
+#[repr(C)]
+#[derive(Copy, Clone, Debug, bytemuck::Pod, bytemuck::Zeroable)]
+pub struct ModelVertex {
+    pub position: [f32; 3],
+}