feat: add 3D model viewer, HUD panel updates, and eskin-finger-sdk submodule

- Add ModelStage component for 3D model rendering
- Update CenterStage to integrate ModelStage viewer
- Expand HudPanel with new functionality
- Add HUD type definitions
- Add je-skin-model.glb 3D model asset
- Add eskin-finger-sdk as git submodule

src/lib/types/hud.ts

@@ -3,6 +3,7 @@ export type LocaleCode = "zh-CN" | "en-US";
 export type WindowControlAction = "minimize" | "toggle-maximize" | "close";
 
 export type ConnectionState = "online" | "connecting" | "offline";
+export type StageViewMode = "webgl" | "model3d";
 
 export type StageStatusTone = "ok" | "warn" | "idle";
 export type HudNoticeTone = "ok" | "warn" | "info";
@@ -86,6 +87,9 @@ export interface HudCopy {
   matrixViewLabel: string;
   matrixViewNumericLabel: string;
   matrixViewDotsLabel: string;
+  stageModeLabel: string;
+  stageModeWebglLabel: string;
+  stageModeModelLabel: string;
   resetConfigLabel: string;
   applyLiveHint: string;
   runtimeReady: string;