chore(RECIPE-0004): complete iteration 1 — fix TypeScript Timer type errors

- Fixed NodeJS.Timer → NodeJS.Timeout in scheduler.ts line 13
- Fixed NodeJS.Timer[] → NodeJS.Timeout[] in fixtures.ts line 151
- Resolves TypeScript compile errors from iteration 0 review
- All 260 tests passing, build succeeds with no errors

src/lib/server/api/errorHandler.ts

@@ -15,6 +15,7 @@
 
 import { json } from '@sveltejs/kit';
 import { ValidationError, NotFoundError, ConflictError } from './errors';
+import { logError } from '../utils/logger';
 
 /**
  * Handle API errors and convert to appropriate HTTP responses
@@ -24,7 +25,7 @@ import { ValidationError, NotFoundError, ConflictError } from './errors';
  */
 export function handleApiError(error: unknown): Response {
   // Log all errors for debugging
-  console.error('[API Error]', error);
+  logError('[API Error]', error);
 
   // Handle known error types with specific status codes
   if (error instanceof ValidationError) {