feat(web): add authenticated app shell

web/src/lib/api-client.ts

@@ -0,0 +1,51 @@
+const apiBase = (): string => import.meta.env.PUBLIC_API_URL || '';
+
+export function apiUrl(path: string): string {
+  return path.startsWith('http') ? path : `${apiBase()}${path}`;
+}
+
+export class ApiError extends Error {
+  status: number;
+  code?: string;
+  detail?: string;
+
+  constructor(status: number, title: string, code?: string, detail?: string) {
+    super(title);
+    this.name = 'ApiError';
+    this.status = status;
+    this.code = code;
+    this.detail = detail;
+  }
+}
+
+export async function toApiError(res: Response): Promise<ApiError> {
+  try {
+    const body = await res.json();
+    return new ApiError(
+      res.status,
+      body.title || body.detail || `Request failed (${res.status})`,
+      body.code,
+      body.detail,
+    );
+  } catch {
+    return new ApiError(res.status, `Request failed (${res.status})`);
+  }
+}
+
+export function jsonHeaders(options?: RequestInit): Headers {
+  const headers = new Headers(options?.headers);
+  if (!headers.has('Content-Type') && !(options?.body instanceof FormData)) {
+    headers.set('Content-Type', 'application/json');
+  }
+  return headers;
+}
+
+export async function apiRequest<T>(path: string, options?: RequestInit): Promise<T> {
+  const res = await fetch(apiUrl(path), {
+    ...options,
+    headers: jsonHeaders(options),
+  });
+  if (!res.ok) throw await toApiError(res);
+  if (res.status === 204) return undefined as T;
+  return res.json() as Promise<T>;
+}