Kit articles (multi-component or cantitate_roa≠1) have expected price
differences between GoMag (commercial) and ROA (component sum).
Skip comparison entirely, mark with kit=True flag for UI badge.
Fix kit detection to use float()!=1 (catches cantitate_roa<1 like 0.5).
Update 3 existing tests + add multi-component kit test.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>