* PPTX: charge repeated chart decodes and sidecar copies to presentation-wide budgets
* address review: count all chart vectors and relationship strings; reject a chart that crosses the presentation limit
* address review: charge chart part names/content types, roll back rejected capture
* address review: bound chart decode work across rejected and repeated references, cache refused sidecar captures
* address review: keep a chart past the presentation chart limits as its original part and closure, so a save writes it back