Patch release within 4.0.x — security and bug fixes only, no source
changes required. Updated both .ruby-version and the Dockerfile ARG
they're explicitly told to keep in sync.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Replace CGI.parse (removed in Ruby 4.0) with Rack::Utils.parse_query
in application controller, sessions controller, and OIDC tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>