drawing_save / drawing_save_as onto a file that another open entry holds
used to succeed: the registry then carried two entries for one path, the
resolver's exact-key shortcut picked the stale entry on document_close, and
the file ended up holding the other document's bytes while both rows still
reported saved: True. Both save paths now refuse before doc.saveas (as
AutoCAD refuses SAVEAS onto an open drawing), the _doc_path setter raises
rather than let two entries share a path, and _resolve_document_key refuses
a shared file on every route — exact key, path and basename — naming the
breach instead of advising "pass the full path" into the unchecked shortcut.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
EnvironmentContract carries every member of the track E interface; the two
drawing_properties_* members are @capability('dwgprops') in this worktree only
and become @abstractmethod when group C's implementations merge.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
