feat(15-03): rewrite login page and auth hooks for OIDC

- Login page redirects to Logto instead of showing credential form
- AuthState uses string id (Logto sub claim) instead of number
- Remove useLogin, useSetup, useChangePassword hooks
- useLogout redirects to /logout (server-side OIDC logout)
- Remove ChangePasswordSection from settings page
- Update UserMenu to use new useLogout API
- Settings page shows API keys section when authenticated

src/client/hooks/useAuth.ts

@@ -1,9 +1,9 @@
 import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
-import { apiDelete, apiGet, apiPost, apiPut } from "../lib/api";
+import { apiDelete, apiGet, apiPost } from "../lib/api";
 
 interface AuthState {
-	user: { id: number } | null;
-	setupRequired: boolean;
+	user: { id: string; email?: string } | null;
+	authenticated: boolean;
 }
 
 export function useAuth() {
@@ -14,43 +14,11 @@ export function useAuth() {
 	});
 }
 
-export function useLogin() {
-	const queryClient = useQueryClient();
-	return useMutation({
-		mutationFn: (data: { username: string; password: string }) =>
-			apiPost<{ username: string }>("/api/auth/login", data),
-		onSuccess: () => {
-			queryClient.invalidateQueries({ queryKey: ["auth"] });
-		},
-	});
-}
-
 export function useLogout() {
-	const queryClient = useQueryClient();
-	return useMutation({
-		mutationFn: () => apiPost<{ success: boolean }>("/api/auth/logout", {}),
-		onSuccess: () => {
-			queryClient.invalidateQueries({ queryKey: ["auth"] });
-		},
-	});
-}
-
-export function useSetup() {
-	const queryClient = useQueryClient();
-	return useMutation({
-		mutationFn: (data: { username: string; password: string }) =>
-			apiPost<{ username: string }>("/api/auth/setup", data),
-		onSuccess: () => {
-			queryClient.invalidateQueries({ queryKey: ["auth"] });
-		},
-	});
-}
-
-export function useChangePassword() {
-	return useMutation({
-		mutationFn: (data: { currentPassword: string; newPassword: string }) =>
-			apiPut<{ success: boolean }>("/api/auth/password", data),
-	});
+	const logout = () => {
+		window.location.href = "/logout";
+	};
+	return { logout };
 }
 
 interface ApiKeyListItem {