feat: transition CI pipeline from TDD RED to GREEN phase

• Update test expectations to require passing tests (GREEN phase)
• Remove error suppression (||true) from build and test commands
• Invert test failure logic: now fails if tests failing vs passing
• Set allow_failure: false for stricter validation
• Update messaging throughout pipeline to reflect GREEN phase

Pipeline now enforces that:

• All builds must succeed
• All tests must pass
• API validation must pass
• Coverage collection must succeed

This aligns with TDD GREEN phase methodology where implementation is complete and tests validate functionality.