X_DB_HANDLE_UNREGISTERED
Means
an entity x g wrote is not in the app's typed database handle
Typical cause
The generated repo.ts reads db.<table>, and packages/db/src/client.ts has no entity set the generator can add to, or packages/db/src/index.ts does not export the handle
Fix
x g entity widget --dry-run --json — lists the files; the finding names the two lines to add to packages/db/src/client.ts