feat: Add demo account creation functionality

- Introduce a new DemoAccountCreator component for generating test accounts with auto-generated credentials.
- Implement useDemoAccountGenerator composable to handle credential generation and state management.
- Update routing to replace the existing login page with the new LoginDemo page for demo account access.
- Add unique-names-generator package to facilitate username generation.

src/composables/useDemoAccountGenerator.ts

@@ -0,0 +1,65 @@
+import { ref } from 'vue'
+import { uniqueNamesGenerator, names, colors, animals } from 'unique-names-generator'
+
+export interface GeneratedCredentials {
+  username: string
+  password: string
+  email: string
+}
+
+export function useDemoAccountGenerator() {
+  const isLoading = ref(false)
+  const error = ref('')
+  const generatedCredentials = ref<GeneratedCredentials | null>(null)
+
+  // Generate a random password
+  function generateRandomPassword(): string {
+    const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!@#$%^&*'
+    let password = ''
+    for (let i = 0; i < 12; i++) {
+      password += chars.charAt(Math.floor(Math.random() * chars.length))
+    }
+    return password
+  }
+
+  // Generate unique username and random password
+  function generateCredentials(): GeneratedCredentials {
+    // Use only 2 dictionaries to keep username shorter
+    const username = uniqueNamesGenerator({
+      dictionaries: [names, colors],
+      separator: '_',
+      length: 2,
+      style: 'lowerCase'
+    })
+    
+    const password = generateRandomPassword()
+    const email = `${username}@demo.local`
+    return { username, password, email }
+  }
+
+  // Generate new credentials
+  function generateNewCredentials(): GeneratedCredentials {
+    const credentials = generateCredentials()
+    generatedCredentials.value = credentials
+    return credentials
+  }
+
+  // Reset state
+  function reset() {
+    isLoading.value = false
+    error.value = ''
+    generatedCredentials.value = null
+  }
+
+  return {
+    // State
+    isLoading,
+    error,
+    generatedCredentials,
+
+    // Actions
+    generateCredentials,
+    generateNewCredentials,
+    reset
+  }
+}