npm: Missing frontend types from npm since v1.48+

### Prerequisites

- [x] I am running the latest version of ComfyUI
- [ ] I have custom nodes enabled

### What happened?

We're missing `index.d.ts` file from `@comfyorg/comfyui-frontend-types` for v1.48.4+, which causes nothing type is exported.

reference: [v1.48.4](https://www.npmjs.com/package/@comfyorg/comfyui-frontend-types/v/1.48.4?activeTab=code) & [v1.47.12](https://www.npmjs.com/package/@comfyorg/comfyui-frontend-types/v/1.47.12?activeTab=code)

### Steps to Reproduce

npm install -D @comfyorg/comfyui-frontend-types

### How is this affecting you?

Missing types.

### ComfyUI Frontend Version

v1.48.4+

### Browser

Node.js v26.7.0

Compare the published @comfyorg/comfyui-frontend-types packages for v1.47.12 and v1.48.4+, then inspect the frontend package and publication configuration that produces them. Confirm how index.d.ts is generated or included, and verify that a newly published package exposes the expected types after npm install.

Written by the indexing model from the issue text.