Add TypeScript declaration files to bnf package

[Copilot]

The atsds-bnf npm package lacked TypeScript type definitions, preventing IntelliSense and type checking in TypeScript projects.

Changes

• Manual declaration file: Created atsds_bnf/index.d.mts with proper type signatures for parse and unparse functions
• Build configuration: Added rollup-plugin-copy to copy .d.mts file to dist/ during build
• Package exports: Added types field to package.json pointing to dist/index.d.mts
• Source preservation: Kept original index.mjs JavaScript implementation without TypeScript conversion

Result

TypeScript users now get proper type checking and autocompletion:

import { parse, unparse } from "atsds-bnf";

// Both functions are now properly typed: (input: string) => string
const ds = parse("a, b -> c");
const dsp = unparse("a\nb\n----\nc");

The declaration file is maintained manually and copied during build, keeping the implementation simple and straightforward while providing full TypeScript support.

[!WARNING]

Original prompt

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This section details on the original issue you should resolve

<filter_complete></filter_complete>

<issue_title>给bnf下面的js包添加.d.mts</issue_title>

<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>给bnf下面的js包添加.d.mts</issue_title>
<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes 给bnf下面的js包添加.d.mts #100

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[hzhangxyz]

不是要你用ts重写你只需要补充一个d mts就行，然后rollup的时候copy过去，pakcage json里标注一下。

[Copilot]

不是要你用ts重写你只需要补充一个d mts就行，然后rollup的时候copy过去，pakcage json里标注一下。

好的，已经改成简单的方式了。现在是：

1. 保持 index.mjs 不变（不用 TypeScript 重写）
2. 手动创建 index.d.mts 声明文件
3. 用 rollup-plugin-copy 在构建时复制到 dist/
4. 在 package.json 里添加了 types 字段

所有测试通过 ✓

Commit: 2d75afc

[Copilot]

Pull request overview

This PR adds TypeScript declaration files to the atsds-bnf npm package to provide type definitions for TypeScript users. The implementation follows the same patterns used in the parent atsds package by using .d.mts extension for ES module type definitions.

Key Changes

• Created a manual TypeScript declaration file (index.d.mts) with properly typed signatures for parse and unparse functions
• Configured the build pipeline to copy the declaration file to the distribution folder using rollup-plugin-copy
• Updated package metadata to expose TypeScript types through the types field

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
bnf/atsds_bnf/index.d.mts	New TypeScript declaration file with function signatures and JSDoc comments for parse and unparse functions
bnf/rollup.config.mjs	Added rollup-plugin-copy plugin to copy declaration file to dist folder during build
bnf/package.json	Added types field, included declaration file in files array, and added rollup-plugin-copy as dev dependency
bnf/package-lock.json	Lockfile updates for rollup-plugin-copy and its transitive dependencies
bnf/atsds_bnf/.gitignore	Updated to track both index.mjs and index.d.mts files (also corrected index.js → index.mjs)

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