fix(types): Improve TypeScript Type Inference

[mast1ff]

This pull request includes updates to improve TypeScript type safety and minor adjustments to logging in the Node.js example. The most important changes involve refining type definitions in the TypeFetcher class and enhancing the clarity of console logging.

TypeScript Type Safety Improvements:

• src/client.ts: Updated the default type parameter of TypeFetcher from Record<string, never> to Record<never, never> to better reflect an empty record.
• src/client.ts: Refined the type of key in the addEndpoint method to explicitly use the template literal type ${Method} ${Path} for improved type inference.
• src/client.ts: Adjusted the request method to simplify the key constraint from string & keyof T to keyof T, aligning with the actual usage and improving readability.

Node.js Example Logging Adjustment:

• examples/nodejs-usage.ts: Updated the logging statement in getUsers to use a type assertion (as any) for response.data to avoid potential TypeScript errors.

[Copilot]

Pull Request Overview

This PR refines TypeScript type definitions in TypeFetcher to improve type inference and adjusts logging in the Node.js example to suppress a TypeScript error.

• Swap default Record<string, never> for Record<never, never> to represent an empty endpoint map
• Narrow template literal types for endpoint keys and simplify the request signature
• Add an explicit cast in the example logging to avoid a type error

Reviewed Changes

Copilot reviewed 2 out of 5 changed files in this pull request and generated 2 comments.

File	Description
src/client.ts	Updated default generic constraint; typed endpoint key and request.
examples/nodejs-usage.ts	Cast response.data to any in the console log for TS compliance.