[solved] Volto theme add-on: src/theme/theme.config not found

Development Plone 6 UI (Volto)
1

theme.config seems to be expected in /theme/ not /src/theme/
log:
/frontend/src/addons/kitconcept-volto-light-theme/theme/theme.config doesn't exist

I added
"theme": "@kitconcept/volto-light-theme",
to package.json of the project and added the package to 'addons' and installed via mrsdeveloper.

I followed Create a Volto theme add-on – Frontend – Volto add-ons — Plone Documentation v6.0.
It seems that I missed a configuration step. Any hints?

2

mrs.developer.json

  "kitconcept-volto-light-theme": {
    "package": "@kitconcept/volto-light-theme",
    "url": "git@github.com:kitconcept/volto-light-theme.git",
    "branch": "main",
    "path": "src"
  }

"path": "src" is essential!