Add biometric authentication enrollment UI

- Create biometric API client with WebAuthn methods
- Add BiometricSettings component for credential management
- Support Face ID, Touch ID, Windows Hello enrollment
- Display list of enrolled credentials with metadata
- Add/remove/rename biometric credentials
- Check browser and platform authenticator support
- Integrate into settings page with animations

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

maternal-web/lib/api/biometric.ts

@@ -0,0 +1,135 @@
+import axios from 'axios';
+
+const API_BASE_URL = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3020';
+
+export interface BiometricCredential {
+  id: string;
+  friendlyName?: string;
+  deviceType?: string;
+  createdAt: Date;
+  lastUsed?: Date;
+  backedUp: boolean;
+}
+
+export const biometricApi = {
+  // Check if user has biometric credentials
+  async hasCredentials(): Promise<{ success: boolean; hasCredentials: boolean }> {
+    const response = await axios.get(`${API_BASE_URL}/api/v1/auth/biometric/has-credentials`, {
+      headers: {
+        Authorization: `Bearer ${localStorage.getItem('accessToken')}`,
+      },
+    });
+    return response.data;
+  },
+
+  // Get all biometric credentials for current user
+  async getCredentials(): Promise<{ success: boolean; credentials: BiometricCredential[] }> {
+    const response = await axios.get(`${API_BASE_URL}/api/v1/auth/biometric/credentials`, {
+      headers: {
+        Authorization: `Bearer ${localStorage.getItem('accessToken')}`,
+      },
+    });
+    return response.data;
+  },
+
+  // Get registration options (start enrollment process)
+  async getRegistrationOptions(friendlyName?: string): Promise<any> {
+    const response = await axios.post(
+      `${API_BASE_URL}/api/v1/auth/biometric/register/options`,
+      { friendlyName },
+      {
+        headers: {
+          Authorization: `Bearer ${localStorage.getItem('accessToken')}`,
+        },
+      }
+    );
+    return response.data;
+  },
+
+  // Verify registration response (complete enrollment)
+  async verifyRegistration(
+    response: any,
+    friendlyName?: string
+  ): Promise<{ success: boolean; credentialId: string; message: string }> {
+    const verifyResponse = await axios.post(
+      `${API_BASE_URL}/api/v1/auth/biometric/register/verify`,
+      { response, friendlyName },
+      {
+        headers: {
+          Authorization: `Bearer ${localStorage.getItem('accessToken')}`,
+        },
+      }
+    );
+    return verifyResponse.data;
+  },
+
+  // Get authentication options (start login process)
+  async getAuthenticationOptions(email?: string): Promise<any> {
+    const response = await axios.post(`${API_BASE_URL}/api/v1/auth/biometric/authenticate/options`, {
+      email,
+    });
+    return response.data;
+  },
+
+  // Verify authentication response (complete login)
+  async verifyAuthentication(
+    response: any,
+    email?: string,
+    deviceInfo?: { deviceId: string; platform: string }
+  ): Promise<{ success: boolean; message: string; user: any; tokens: any }> {
+    const verifyResponse = await axios.post(
+      `${API_BASE_URL}/api/v1/auth/biometric/authenticate/verify`,
+      { response, email, deviceInfo }
+    );
+    return verifyResponse.data;
+  },
+
+  // Delete a credential
+  async deleteCredential(credentialId: string): Promise<{ success: boolean; message: string }> {
+    const response = await axios.delete(
+      `${API_BASE_URL}/api/v1/auth/biometric/credentials/${credentialId}`,
+      {
+        headers: {
+          Authorization: `Bearer ${localStorage.getItem('accessToken')}`,
+        },
+      }
+    );
+    return response.data;
+  },
+
+  // Update credential name
+  async updateCredentialName(
+    credentialId: string,
+    friendlyName: string
+  ): Promise<{ success: boolean; message: string }> {
+    const response = await axios.patch(
+      `${API_BASE_URL}/api/v1/auth/biometric/credentials/${credentialId}`,
+      { friendlyName },
+      {
+        headers: {
+          Authorization: `Bearer ${localStorage.getItem('accessToken')}`,
+        },
+      }
+    );
+    return response.data;
+  },
+
+  // Check if WebAuthn is supported in this browser
+  isSupported(): boolean {
+    return (
+      typeof window !== 'undefined' &&
+      window.PublicKeyCredential !== undefined &&
+      typeof window.PublicKeyCredential === 'function'
+    );
+  },
+
+  // Check if platform authenticator (Face ID, Touch ID, Windows Hello) is available
+  async isPlatformAuthenticatorAvailable(): Promise<boolean> {
+    if (!this.isSupported()) return false;
+    try {
+      return await window.PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable();
+    } catch {
+      return false;
+    }
+  },
+};