PathBasedClient cannot be (directly) used with generated paths

[gzm0]

Description

Typescript fails:

│ test/index.test.ts(1888,58): error TS2344: Type 'paths' does not satisfy the constraint 'Record<string, Record<HttpMethod…
│   Index signature for type 'string' is missing in type 'paths'.

Reproduction

import type { PathBasedClient } from "../src/index.js";
import type { paths } from "./fixtures/api.js";

PathBasedClient<paths> // this line fails to compile

Expected result

Compiles

Checklist

• I’m willing to open a PR (see CONTRIBUTING.md)