Adding ht-github-attachment-reupload to hermes-talaria — Copying GitHub Attachments Across Repos via the Authenticated Browser

I added ht-github-attachment-reupload to hermes-talaria: a skill that copies original attachments on GitHub issues, PRs, and discussions to a different repository. GitHub serves attachments against the posting repo's permissions, so re-posting only the body text to another repo breaks images and file downloads for viewers who lack access to the original repo. This skill reuploads the originals through the authenticated browser UI so the destination can serve them under its own permissions. The write-up walks through the design decisions I made while reviewing the PR.