This is not the way Ward 7 Councilmember Vince Gray’s storied political career was supposed to end. It was a given that Gray’s various health challenges would deprive him of the sort of graceful ride into the sunset that might otherwise have been afforded to someone with his three-decade-long career. Gray announced Thursday through a spokesperson that he’s experiencing “early-stage, age-related dementia” and he will step back from Council duties until his term concludes at the end of the year, a sad but perhaps inevitable development for the former mayor after he endured strokes and other health problems. The details below the headlines are another matter entirely.