feat(io): FBXEXPORT writes the drawing's 3D meshes as binary FBX

FBXEXPORT (also EXPORTFBX) saves every 3D mesh of the drawing (solids,
surfaces and meshes, at full display resolution) as a binary FBX 7.4
file for visualisation tools: one model per object with its geometry,
face normals and a material in its display colour. Axes stay Z-up and
the unit scale follows the drawing's insertion units.

Refs #1502

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

locales/ru-RU/opencadstudio.ftl

@@ -286,6 +286,11 @@ command-copy =
     .mode = COPY  Задайте режим копирования [Single/Multiple] <Multiple>:
 
 common =
+    .fbxexport-exported-to = FBXEXPORT: экспортируется в "__ocs_fmt_0__"
+    .fbxexport-no-3d-mesh-data-in-this-drawing = FBXEXPORT: в этом чертеже нет данных 3D-сети.
+    .fbxexport-error = FBXEXPORT: __ocs_fmt_0__
+    .export-fbx = { manage.export } FBX
+    .fbx-files = { common.files } (FBX)
     .options-hpassoc = Новые штриховки следуют за контурами (HPASSOC)
     .options-show-ribbon = Показывать ленту (RIBBON / RIBBONCLOSE)
     .options-show-menu-bar = Показывать строку меню (MENUBAR)