Cannot read 'definition.pbism'. Required artifact is missing.

The semantic model is missing its definition.pbism file.

Why it happens

• definition.pbism was never created, or was deleted.
• An incomplete PBIP scaffold.

How to fix it

1. Create definition.pbism in the .SemanticModel folder (the small JSON with the model version/settings).
2. Regenerate the model folder from a known-good PBIP template.
3. Clear the Power BI Desktop cache if the error persists after the file exists.