1. Problem with types file index.d.ts:

As per Node documentation the "types" entry field in package.json isn't used by the node runtime.
On Windows, vscode is complaining about decalaration file:

There are types at /node_modules/rehype-citation/dist/node/index.d.ts', but this result could not be resolved when respecting package.json "exports". the 'rehype-citation' library may need to update its package.json or typings.

As shown in Node documentation,

Since custom package conditions require clear definitions to ensure correct usage, a list of common known package conditions and their strict definitions is provided below to assist with ecosystem coordination.

"types" - can be used by typing systems to resolve the typing file for the given export. This condition should always be included first.

So we need to add index.d.ts file to exports to solve this problem., like below

  "exports": {
    ".": {
    + "types": "./dist/node/index.d.ts",
      "node": "./dist/node/rehype-citation.mjs",
      "default": "./dist/browser/rehype-citation.mjs"
    },
    ...
  }

2. Bug: Problem with [^ref] not working on node.
   It's seems that the problem is due to a poorly positioned closing curly brace.