ExcelJS 4.4.0 expands three constructs into one object per cell or column
at load time, so a few KB admitted as one cell could cost a gigabyte:
- a <mergeCell> now costs its full area against the per-sheet and total
cell caps, and a ref that does not parse is refused
- a <col> whose min or max is past 16384 is refused
- the worker loads with ignoreNodes: ['dataValidations']; the preview
never shows validations, and a whole-column dropdown took 5 s
The XML counter now scans up to the last complete tag and carries the
rest, so a merge or col tag cut by an inflate-chunk edge is read whole.
A central-directory compressedSize that runs past the file is refused,
since the ratio cap divides by it.
The renderer and core axis offsets use prefix sums with a binary search
instead of walking every override per call.
Aamer Akhter
bfab172608