fix(security): resolve FLAW-08 with token_version invalidation and jwt blacklist

frontend/src/lib/api.ts

@@ -117,6 +117,18 @@ export const api = {
     return request<AuthStatus>('/api/v1/auth/status');
   },
 
+  async logout(): Promise<void> {
+    try {
+      await request<{ success: boolean }>('/api/v1/auth/logout', { method: 'POST' });
+    } finally {
+      clearToken();
+    }
+  },
+
+  async revokeAllSessions(): Promise<void> {
+    await request<{ success: boolean }>('/api/v1/auth/revoke-all', { method: 'POST' });
+  },
+
   async completeSetup(payload: {
     email: string;
     password: string;