FIX: Reload from disk fails when 3MF stores source as filename only

[ClusterM]

Summary

• Reload from disk often showed Unable to reload for models imported from a 3MF (for example a FreeCAD export), even when the file on disk loaded fine.
• 3MF projects store source.input_file as a filename only (tpu_tube-Roller.3mf) by design (FullPathSources is off so shared projects do not leak full paths). After the same file is read again, the new volume gets the absolute path. The matcher used == on those strings, so a valid reload was rejected.
• The name fallback never ran in this case either: it required the part name to equal the source filename (Roller vs tpu_tube-Roller.3mf). The 3MF object name and the part name on the plate already matched (Roller).

Change

In Plater::priv::reload_from_disk():

• Compare source files by filename (case-insensitive), not by the full stored string.
• If the stored object/volume slot does not match, search the just-loaded model by part name. Do not require that name to be the source filename.

[Haidiye00]

Hello, please provide the GIF tests before and after the modification. Thank you

[ClusterM]

Hello, please provide the GIF tests before and after the modification. Thank you

Before the fix:

After the fix:

[Haidiye00]

approve