Fixes #6519 On core24, `snap/gui/` is no longer copied into the prime dir before desktop files are read, so `desktop: meta/gui/app.desktop` (and `snap/gui/app.desktop`) fails to pack. This maps those two prefixes back to the project's `snap/gui/` dir. The project file still wins over one a part puts in `prime/snap/gui/`, as before, and other paths are unchanged. The error also shows the path from the project again. I based this on `hotfix/9.2` and added a 9.2.2 release note. Happy to move it to `main` if you prefer. Tested with a real core24 pack in destructive mode (fails on the base branch, works with the fix) and new unit tests. I ran ruff, ty, codespell and the tests in a container instead of `make lint && make test`. --- - [x] I've followed the [contribution guidelines](https://github.com/canonical/snapcraft/blob/main/CONTRIBUTING.md). - [x] I've signed the [CLA](http://www.ubuntu.com/legal/contributors/). - [ ] I've successfully run `make lint && make test`. - [ ] I've added or updated any relevant documentation. - [ ] In documents I changed, I [added a meta description](https://canonical-starflow.readthedocs-hosted.com/how-to/add-a-page-meta-description/) if one was missing. - [x] I've updated the relevant release notes.