* Multiline attributes: read, draw and save their text
A multiline attribute (DXF attribute type 2, or 4 for a definition) has its
text as embedded MTEXT after its own groups (`101 Embedded Object`); its own
group 1 is empty. CADCraft read only the own groups, so the attribute drew
nothing, and a save wrote it back empty: its text was lost.
- `Attrib::multiline` keeps the multiline text; `text.value` holds its plain
text, which ATTEDIT and the other value editors change; an edited value
replaces the contents (`Attrib::multiline_text`).
- DXF read: ATTRIB and ATTDEF split at the marker; the MTEXT parsing is
shared with MTEXT entities (`mtext_from`).
- Drawn as multiline text; ZOOM Extents counts it.
- DXF write (2007 and later; earlier versions get one line): attribute type,
alignment point and the embedded MTEXT, only what differs from unrotated
text, as AutoCAD writes it.
- INSERT and ATTSYNC give references the definition's multiline text placed
with them; MOVE/ROTATE/SCALE, Properties rotation and scale, annotative
scaling and FLATTEN carry it.
- Tests: synthetic multiline ATTDEF and ATTRIB (read, drawn, saved, edited,
pre-2007 save, damaged embedded groups); engine INSERT, MOVE, ATTEDIT and
ATTSYNC.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* Multiline attributes: read MTEXT direction from its own groups (#667, as #834 does)
#834 moves these lines' fix into the MTEXT reader; the same fix in the shared
mtext_from keeps the two compatible.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: Cody Vogt <18035288+codyvogt@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>
