feat(modify): TXTEXP turns text into its character outlines

TXTEXP replaces each selected TEXT and MTEXT with one polyline per
glyph contour, on the text's layer and with its properties: a
lightweight polyline for flat text, a 3D polyline for tilted text.
The outlines come from the same glyph tessellation the text renders
with, so stroke fonts give their strokes and outline fonts their
closed contours.

Refs D#1665

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

locales/ru-RU/opencadstudio.ftl

@@ -285,6 +285,7 @@ command-copy =
     .mode = COPY  Задайте режим копирования [Single/Multiple] <Multiple>:
 
 common =
+    .txtexp-no-text-selected = TXTEXP: текст не выбран.
     .angle-override-shown = Переопределение угла: __ocs_fmt_0__
     .plot-preview-task = Предварительный просмотр печати
     .link-a-csv-data-source = Связать источник данных CSV