v0.4.5

Release v0.4.5: action-gh-release v3 (Node 24); single-source version

- Pin softprops/action-gh-release to v3 (runs on node24), clearing the
  Node 20 deprecation warning.
- Drop the stale version field from package.json; manifest.json is the
  sole version source and the build already reads it.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

v0.4.4

Release v0.4.4: bump manifest version; README free-tier wording

No plugin code change since v0.4.3; cuts a fresh release so the
published artifacts track HEAD.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

v0.4.3

Initial commit: Causal Map for Zotero plugin, docs, and release workflow

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>