Main now aborts an export when a stored hidden layer can no longer be
applied (#876). Vector export follows it: a layer hidden in Object Layer
Options that the placed PDF doesn't have, because the file has no layers
or was relinked, fails with an error naming the file instead of exporting
everything visible. The image-path tests for oversized images and
undecodable content export as PDF/A-2b, which still rasterizes placed
PDFs with hidden layers.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Integrate current main (d8d78851) without rewriting the contributor's commits, retaining craft-libs 9f75d3dc.
Accept literal null trailer entries while rejecting actual or ambiguous encryption/hybrid markers. Structurally inspect bounded xref/trailer history instead of adopting trailer-looking comments. Preflight all selected source variants before editing/undo; preserve reset-to-defaults. Suppress stale unrewritable canvas overrides rather than revealing source content. Keep conservative all-content crop fallback without overcropping layerless/null stubs.
Validation: cargo xtask ci, all 9 gates passed; 3062 tests passed, 6 skipped; all 16 WASM-safe crates checked. 17 supported variants passed independent qpdf, logical preservation and Poppler pixel checks; 6 unsupported/repair-only cases refused. Direct-harness Claude Opus 5 reviewed the exact main-relative delta with no blocking findings.
No native-format changes or unrelated layer features. Synthetic regression fixtures are generated in test code.
