feat(api): add custom ApiError class for error handling

- Create ApiError class extending Error with status code support
- Enables better error handling and status code management in API calls

web/src/lib/errors.ts

@@ -0,0 +1,12 @@
+/**
+ * Custom error class for API errors
+ */
+export class ApiError extends Error {
+	status: number
+
+	constructor(message: string, status = 500) {
+		super(message)
+		this.name = "ApiError"
+		this.status = status
+	}
+}