Stabilizing the Core: General Cleanup, Rails 8 implementation, Ruby 4.0.1 Pin, and Safer Public Pages

We focused on stability and upgrade readiness here: moved the app to Rails 8.1.2, upgraded Ruby to 4.0.1 and pinned it in the Gemfile, all while resolving upgrade noise live in production. Total downtime: like 2 minutes. Because a ":" got deprecated in favor of "{" somewhere in Rails lol.

Also included in this string of updates: tightened S3 presigning behavior, added a report-only CSP, and ensured pagination/ordering on the public indexes (docs, games, projects, videos, blog posts) to keep the UI responsive even with large datasets. We also expanded seed data so the app can be stress-tested with realistic volume.

Later we hardened the view layer to avoid runtime crashes when data is missing or partially configured. Documents, calendar, dashboard, and the public pages (home/about/contact) now guard against nils and missing YAML content. We also cleaned up games progress JSON handling and kept rewards behavior predictable while preparing for future reward types. Overall the app is sturdier, faster under load, and safer to evolve without breaking core screens.