Update root and documentation bundle dependencies

[joelhawksley]

Summary

• Run bundle update for the root bundle and the documentation bundle.
• Update Gemfile.lock and docs/Gemfile.lock within the existing Gemfile constraints, including Rails 8.1.4 in the root bundle and ActiveSupport 8.1.4 in the docs bundle.
• Leave both Gemfiles and the appraisal lockfiles unchanged.
• Baseline existing findings newly reported by Audition 0.4.1, keeping CI enforcement for future findings.
• Remove three obsolete RuboCop directives and a redundant line continuation flagged by the updated Standard rules.

Validation

• bundle exec rake all_tests with Ruby 4.0.6: 640 component tests, 5 engine tests, and 8 RSpec examples passed; eager loading passed.
• bundle exec jekyll build in docs with Ruby 3.3.12: passed.
• bundle exec audition . --static-only --plain: passed, with 79 findings baselined.
• bundle exec standardrb -r rubocop-md and bundle exec erb_lint --lint-all: passed.
• Rendering tests after lint cleanup: 141 tests passed.