Rails 8.1.x

[JPrevost]

Developer

• All new ENV is documented in README
• All new ENV has been added to Heroku Pipeline, Staging and Prod
• ANDI or Wave has been run in accordance to
  our guide and
  all issues introduced by these changes have been resolved or opened as new
  issues (link to those issues in the Pull Request details above)
• Stakeholder approval has been confirmed (or is not needed)

Code Reviewer

• The commit message is clear and follows our guidelines
  (not just this pull request message)
• There are appropriate tests covering any new functionality
• The documentation has been updated or is unnecessary
• The changes have been verified
• New dependencies are appropriate or there were no changes

Requires database migrations?

NO

Includes new or updated dependencies?

YES

[qltysh]

All good ✅

[Copilot]

Pull request overview

This PR upgrades the application to Rails 8 and aligns the repository’s dependencies, configs, and static error pages with the Rails 8 defaults and ecosystem changes.

Changes:

• Upgrade Rails from 7.2.x to 8.0.x and update locked gem versions accordingly (including updating mitlibraries-theme to a Rails 8-compatible branch).
• Refresh Rails public error pages (400/404/422/500/406) and update the app icon SVG.
• Adjust runtime/config defaults for Rails 8 (Puma Solid Queue plugin toggle, environment config tweaks, parameter filtering additions, and bin script updates).

Reviewed changes

Copilot reviewed 15 out of 20 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
renovate.json	Expand Renovate allowed version ranges for Ruby and Rails upgrades.
README.md	Update development notes (and should document new runtime ENV introduced in this PR).
Gemfile	Bump Rails requirement, update theme source, remove obsolete pins/tools.
Gemfile.lock	Reflect Rails 8 and dependency updates.
config/application.rb	Load Rails 8 defaults and minor syntax update.
config/puma.rb	Add optional Solid Queue-in-Puma plugin toggle.
config/environments/development.rb	Update development caching/logging defaults for Rails 8.
config/environments/test.rb	Update test environment defaults (static file server headers, etc.).
config/environments/production.rb	Update production defaults (SSL assumptions, caching headers, deprecation reporting, etc.).
config/initializers/filter_parameter_logging.rb	Add additional sensitive parameter filters (cvv/cvc).
config/initializers/assets.rb	Remove commented boilerplate.
public/400.html	Add custom static 400 error page (Rails 8-style).
public/404.html	Replace default 404 page with custom static page.
public/406-unsupported-browser.html	Replace default 406 page with custom static page.
public/422.html	Replace default 422 page with custom static page.
public/500.html	Replace default 500 page with custom static page.
public/icon.svg	Update icon geometry/size.
bin/setup	Start bin/dev by default after setup (unless --skip-server).
bin/dev	Add a minimal dev runner invoking rails server.

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[Copilot]

Pull request overview

Copilot reviewed 21 out of 28 changed files in this pull request and generated 8 comments.

[jazairi]

Seems like we'll need to upgrade Devise to fix the deprecation warnings, but that feels like a problem to fix before 8.2, not in this PR. Otherwise, all seems well with this, both locally and in the PR build.

[JPrevost]

@jazairi Correct on Devise, I meant to note that and forgot sorry!