feat: add pseudo-authorization with code word

User must enter code word "пупырка" to access the app.
Auth state persisted in localStorage.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/app/app.component.ts

@@ -1,14 +1,116 @@
-import { Component } from '@angular/core';
+import { Component, signal } from '@angular/core';
+import { FormsModule } from '@angular/forms';
 import { ToastModule } from 'primeng/toast';
 import { AppLayoutComponent } from './components/app-layout/app-layout.component';
 
+const AUTH_KEY = 'test-x6-auth';
+const CODE_WORD = 'пупырка';
+
 @Component({
   selector: 'app-root',
   standalone: true,
-  imports: [ToastModule, AppLayoutComponent],
+  imports: [FormsModule, ToastModule, AppLayoutComponent],
   template: `
+    @if (authorized()) {
       <p-toast />
       <app-layout />
+    } @else {
+      <div class="login-wrapper">
+        <div class="login-card">
+          <h2>Детальная схема связей</h2>
+          <p>Введите кодовое слово для входа</p>
+          <input
+            type="password"
+            [(ngModel)]="inputValue"
+            (keydown.enter)="tryLogin()"
+            placeholder="Кодовое слово"
+            [class.error]="showError()"
+            autofocus
+          />
+          @if (showError()) {
+            <span class="error-text">Неверное кодовое слово</span>
+          }
+          <button (click)="tryLogin()">Войти</button>
+        </div>
+      </div>
+    }
+  `,
+  styles: `
+    .login-wrapper {
+      display: flex;
+      align-items: center;
+      justify-content: center;
+      height: 100vh;
+      background: #f5f5f5;
+    }
+    .login-card {
+      background: #fff;
+      border-radius: 8px;
+      padding: 32px;
+      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.12);
+      text-align: center;
+      width: 320px;
+    }
+    .login-card h2 {
+      margin: 0 0 8px;
+      font-size: 18px;
+      color: #333;
+    }
+    .login-card p {
+      margin: 0 0 20px;
+      color: #888;
+      font-size: 13px;
+    }
+    .login-card input {
+      width: 100%;
+      padding: 10px 12px;
+      border: 1px solid #d9d9d9;
+      border-radius: 6px;
+      font-size: 14px;
+      outline: none;
+      box-sizing: border-box;
+      transition: border-color 0.2s;
+    }
+    .login-card input:focus {
+      border-color: #4096ff;
+    }
+    .login-card input.error {
+      border-color: #ff4d4f;
+    }
+    .error-text {
+      display: block;
+      color: #ff4d4f;
+      font-size: 12px;
+      margin-top: 6px;
+    }
+    .login-card button {
+      margin-top: 16px;
+      width: 100%;
+      padding: 10px;
+      background: #4096ff;
+      color: #fff;
+      border: none;
+      border-radius: 6px;
+      font-size: 14px;
+      cursor: pointer;
+      transition: background 0.2s;
+    }
+    .login-card button:hover {
+      background: #1677ff;
+    }
   `,
 })
-export class AppComponent {}
+export class AppComponent {
+  authorized = signal(localStorage.getItem(AUTH_KEY) === 'true');
+  showError = signal(false);
+  inputValue = '';
+
+  tryLogin() {
+    if (this.inputValue.trim().toLowerCase() === CODE_WORD) {
+      localStorage.setItem(AUTH_KEY, 'true');
+      this.authorized.set(true);
+    } else {
+      this.showError.set(true);
+    }
+  }
+}