feat: 实现大模型模型列表与供应商管理，并接入 Playwright 测试

补齐 LLM 子菜单路由，落地模型列表与供应商管理页面交互，同时引入功能与视觉回归用例以便后续页面持续验证。

Co-authored-by: Cursor <cursoragent@cursor.com>

e2e/fixtures/auth.ts

@@ -0,0 +1,19 @@
+import { expect, test as base } from '@playwright/test';
+
+export const test = base.extend({
+  page: async ({ page }, applyFixture) => {
+    await page.addInitScript(() => {
+      localStorage.setItem(
+        'user-store',
+        JSON.stringify({
+          state: { token: 'e2e-token' },
+          version: 0,
+        }),
+      );
+    });
+
+    await applyFixture(page);
+  },
+});
+
+export { expect };