Log Level Reduction and Integration Test Tagging

What Was Built

• Set config.log_level = :warn in test environment to eliminate ~95MB of debug log IO per test run
• Created lib/tasks/test_fast.rake providing test:fast rake task that excludes integration/ and system/ directories
• Verified all 4 integration test files already in test/integration/ (no moves needed)
• Full suite: 1033 runs, 0 failures; Fast mode: 1022 runs, 0 failures

Files Modified

• test/dummy/config/environments/test.rb — added config.log_level = :warn after config.cache_store = :null_store
• lib/tasks/test_fast.rake — new rake task test:fast using Dir glob to exclude integration and system test files

Deviations

• Plan specified --exclude-pattern flag for minitest but this flag does not exist in Rails/Minitest. Replaced with Dir glob approach that rejects test/integration/ and test/system/ paths (DEVN-01 Minor).
• Also excluded test/system/ from fast mode since bin/rails test already excludes system tests by default — this makes test:fast equivalent to bin/rails test minus integration tests.
• Rake task accessible as bundle exec rake app:test:fast from engine root (engine prefixes with app:).