Claim model/x-ply so cce-files can open PLY files here

shared-mime-info registers no PLY type, so cce-files maps .ply to
model/x-ply by extension; the entry has to claim it for the default
handler lookup to find cce-model.

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

 cce-model.desktop | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cce-model.desktop b/cce-model.desktop
index 4f363a7..6f95bfa 100644
--- a/cce-model.desktop
+++ b/cce-model.desktop
@@ -7,5 +7,5 @@ Exec=cce-model %f
 Icon=cce-model
 Terminal=false
 Categories=Graphics;3DGraphics;Viewer;
-MimeType=model/stl;model/x.stl-ascii;model/x.stl-binary;application/sla;model/obj;model/gltf+json;model/gltf-binary;
+MimeType=model/stl;model/x.stl-ascii;model/x.stl-binary;application/sla;model/obj;model/gltf+json;model/gltf-binary;model/x-ply;
 NoDisplay=false