Ghostwriter v6: Introducing Collaborative Editing

Ghostwriter v6.0.0-rc1 introduces real-time collaborative editing for observations, findings, and report fields via the YJS/Tiptap/Hocuspocus stack integrated with the existing GraphQL/Hasura backend, along with inline image previews, modern frontend tooling (Vite, React, TypeScript), and infrastructure updates; it also upgrades Django to 4.2 and PostgreSQL to 16.4 (requiring a pg-upgrade step) and adds Nginx in development, all released as a candidate for testing and feedback.