feat: 3D ARRAY (ARRAY3D / 3DARRAY command)

Three-dimensional rectangular array: prompts for rows, columns, levels
and their respective spacings, then generates copies translated along
X (columns), Z (rows in drawing plane), and Y (levels / height).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ROADMAP.md

@@ -294,7 +294,7 @@ Underlay (PDF/DWF/DGN)
 | Solid3D tessellation (acadrust ACIS) | ✅ |
 | Boolean operasyonlar (UNION/SUBTRACT/INTERSECT) | ⬜ |
 | EXTRUDE / REVOLVE / SWEEP / LOFT | ⬜ |
-| 3D ARRAY | ⬜ |
+| 3D ARRAY | ✅ |
 | STL / STEP dışa aktarma | ⬜ |
 
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