Two in-canvas confirmations on the Save-As path:
- AEC/Civil drop warning: when the drawing carries unsupported AEC/Civil
(application) objects that survive only as verbatim source-version bytes,
saving to a different version or to DXF would silently drop them. The
dialog reports the count and offers "Save in source version" (keep) vs
"Save anyway" (drop). Same-version DWG saves are lossless and skip it.
- Overwrite confirmation: when the chosen filename already exists in the
target folder, "Replace" / "Cancel" before clobbering it.
The two chain (AEC first, then overwrite) via per-flow acknowledgement flags
reset whenever the Save dialog opens or closes. Detection is a new
io::dropped_on_save_count over the document's Unknown (raw-passthrough)
objects/entities.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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