What a trans­for­ma­tion for the flam­boy­ant musi­cian King Charles. Last year I saw him per­form in a church in Hack­ney, where a polite crowd clus­tered round the stage, sup­ping wine and sway­ing gen­tly. A year on, and he’s head­lin­ing at Shep­herd’s Bush. The place seems rammed to the rafters with the most excit­ed crowd I’ve…