feat(auth): implement option 3 architecture - server InteractiveServer login + client WASM dashboard

- Add Server.AddInteractiveServerComponents() + AddInteractiveServerRenderMode()
- Create Server AuthLayout for login form (MudBlazor)
- Implement LoginSimple.razor with @rendermode InteractiveServer in Server project
- Update App.razor: CascadingAuthenticationState + Router with AppAssembly=Server
- Fix Client MudBlazor Providers in MainLayout + AuthLayout
- Update Playwright tests: use dynamic selectors for MudTextField (auto-generated IDs)
- Build: 0 errors, 0 warnings
- API: /api/auth/login fully operational (200 OK confirmed)
- Playwright E2E test: 1 passed

Architecture:
/login    → Server InteractiveServer (MudBlazor form)
/         → Client WebAssembly (Dashboard)
/api/*    → Server Endpoints

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

tests/e2e/console-check.spec.ts

@@ -0,0 +1,64 @@
+import { test } from '@playwright/test';
+
+test('브라우저 콘솔 에러 확인', async ({ page }) => {
+  const consoleMessages: string[] = [];
+  const jsErrors: string[] = [];
+
+  page.on('console', msg => {
+    console.log(`[${msg.type().toUpperCase()}] ${msg.text()}`);
+    if (msg.type() === 'error') {
+      jsErrors.push(msg.text());
+    }
+    consoleMessages.push(`${msg.type()}: ${msg.text()}`);
+  });
+
+  page.on('pageerror', error => {
+    console.log(`[PAGE ERROR] ${error.message}`);
+    jsErrors.push(error.message);
+  });
+
+  console.log('\n로그인 페이지 접근...');
+  await page.goto('http://localhost:5265/login');
+  await page.waitForLoadState('networkidle');
+  await page.waitForTimeout(2000);
+
+  console.log('\n입력 및 로그인...');
+  const usernameInput = page.locator('input[type="text"]').first();
+  const passwordInput = page.locator('input[type="password"]');
+  const loginButton = page.locator('button:has-text("로그인")');
+
+  await usernameInput.fill('admin');
+  await passwordInput.fill('admin');
+
+  console.log('로그인 버튼 클릭...');
+  await loginButton.click();
+
+  await page.waitForTimeout(3000);
+
+  console.log('\n\n╔════════════════════════════════════════════════════╗');
+  console.log('║            콘솔 메시지 요약                       ║');
+  console.log('╚════════════════════════════════════════════════════╝\n');
+
+  console.log(`총 메시지: ${consoleMessages.length}`);
+  console.log(`JavaScript 에러: ${jsErrors.length}`);
+
+  if (jsErrors.length > 0) {
+    console.log('\n❌ 감지된 에러:');
+    jsErrors.forEach((err, i) => {
+      console.log(`  ${i + 1}. ${err}`);
+    });
+  } else {
+    console.log('\n✅ JavaScript 에러 없음');
+  }
+
+  // Blazor 관련 콘솔 메시지
+  const blazorMessages = consoleMessages.filter(m => m.toLowerCase().includes('blazor'));
+  if (blazorMessages.length > 0) {
+    console.log('\n🔵 Blazor 메시지:');
+    blazorMessages.forEach(msg => {
+      console.log(`  - ${msg}`);
+    });
+  }
+
+  console.log('\n최종 URL:', page.url());
+});