Stop tracking accidental node_modules symlink

Details

The previous commit's `git add -A` staged a local `node_modules` symlink
(created to share the parent worktree's deps for the build). The repo's
`.gitignore` uses `node_modules/` (trailing slash), which matches a directory
but not a symlink, so it slipped in. In CI that symlink makes `pnpm install`
fail with `ENOTDIR: ... mkdir '.../node_modules'`, which cascaded into every
Node/Ruby job (build, frontend tests, changelog tests). Untrack it; the CSS/TS
changes are unaffected.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YB1axhX3kbHCFJbX7LhfH8

Files changed (1)