MAESTRO: fix strict tsc compile

Auto Run Docs/SpecKit-web-header-analyzer-Phase-01-Project-Setup.md

@@ -74,5 +74,5 @@ The hacker-themed dark colour palette (from spec FR-14):
 - [x] Frontend starts with `npm run dev` and renders a blank page
 - [x] Linting passes on both sides (`ruff check backend/`, `npx eslint src/`, `npx prettier --check src/`)
 - [x] Playwright test runner executes with `npx playwright test` (no tests yet, but config loads without error)
-- [ ] TypeScript compilation succeeds with zero errors in strict mode
+- [x] TypeScript compilation succeeds with zero errors in strict mode
 - [ ] Run `/speckit.analyze` to verify consistency

frontend/src/lib/api-client.ts

@@ -39,7 +39,10 @@ export interface StreamRequestOptions<TBody, TEvent> {
 }
 
 export interface ApiClient {
-  request<TResponse>(path: string, init?: RequestInit & { body?: unknown }): Promise<TResponse>;
+  request<TResponse>(
+    path: string,
+    init?: Omit<RequestInit, "body"> & { body?: unknown },
+  ): Promise<TResponse>;
   get<TResponse>(path: string, init?: RequestInit): Promise<TResponse>;
   post<TResponse, TBody>(path: string, body: TBody, init?: RequestInit): Promise<TResponse>;
   stream<TBody, TEvent>(path: string, options: StreamRequestOptions<TBody, TEvent>): Promise<void>;
@@ -228,7 +231,7 @@ export const createApiClient = (options: ApiClientOptions = {}): ApiClient => {
 
   const request = async <TResponse>(
     path: string,
-    init: RequestInit & { body?: unknown } = {},
+    init: Omit<RequestInit, "body"> & { body?: unknown } = {},
   ): Promise<TResponse> => {
     const url = resolveUrl(baseUrl, path);
     const { body, headers, ...rest } = init;