debug(clazz-e2e): add page state debugging for CI view-toolbar failure

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/clazz-dual-view.spec.ts

@@ -31,6 +31,19 @@ test.describe('排课双视图切换（阿难账号）', () => {
     await expect(page.locator('#app')).toBeVisible({ timeout: 60_000 });
     await page.waitForTimeout(3000);
 
+    // Debug: capture page state before assertion
+    const debugUrl = page.url();
+    console.log(`[debug] URL after login+goto: ${debugUrl}`);
+    const pageTitle = await page.title().catch(() => 'N/A');
+    console.log(`[debug] Page title: ${pageTitle}`);
+    const bodyText = await page.evaluate(() => document.body?.innerText?.substring(0, 500) || 'no body');
+    console.log(`[debug] Body text (first 500): ${bodyText.replace(/\n/g, '↵')}`);
+    const appHtml = await page.evaluate(() => {
+      const app = document.getElementById('app');
+      return app ? app.innerHTML.substring(0, 800) : 'no #app';
+    });
+    console.log(`[debug] #app innerHTML (first 800): ${appHtml}`);
+
     // Check toggle buttons exist
     const toggleBar = page.locator('.view-toolbar');
     await expect(toggleBar).toBeVisible({ timeout: 10_000 });