Headline score analyzer

The ten rules are heuristics, not search-engine internals: they reward the shape that reads well in results and penalize vagueness, shouting, and hype. Search engines cut titles at their own pixel widths, which vary by device and viewport, so treat the truncation preview as an approximation of a desktop result. The pixel measure is honest canvas text metrics for 20px Arial; other fonts and mobile layouts will cut at different points. Keyword rules check placement, not intent.