Snapcraft - folder witch_spells are mounted with the snap but never copy to the final location

[cosmic-zip]

Issue: witch_spells Folder Not Copied to Host System in Snapcraft

Description:
During the Snapcraft build process, the folder witch_spells is correctly mounted within the .snap package and appears at the location /var/witch_craft/witch_spells when the package is unpacked using unsquashfs. However, the contents of witch_spells are not being copied to the expected destination on the host system upon installation, which prevents their access by the application.

Steps to Reproduce:

1. Build the .snap package with Snapcraft, ensuring the witch_spells folder is included.
2. Verify the contents of the .snap file using unsquashfs and confirm that witch_spells is present at /var/witch_craft/witch_spells.
3. Install the snap on the host system and attempt to access /var/witch_craft/witch_spells from the host environment.
4. Notice that witch_spells is missing on the host, even though it appears in the .snap package.

Expected Behavior:
The witch_spells folder should be copied to /var/witch_craft/witch_spells on the host system during installation, making its contents accessible to the application.

Observed Behavior:
The witch_spells folder remains within the .snap package but is not copied to the final location on the host.

Potential Causes:

1. Snapcraft Configuration: The Snapcraft YAML configuration might lack proper directives to ensure the witch_spells folder is copied to the final location.
2. Confinement Issues: If the snap uses strict confinement, it may not have the necessary permissions to copy files to /var.
3. Snap Layouts or Bind Mounts: Snap layouts or bind mounts might be misconfigured, preventing witch_spells from being linked to the host system.

Suggested Solution:

1. Verify Snapcraft YAML Configuration: Ensure the witch_spells directory is properly defined in the Snapcraft YAML under the layout section to bind it to /var/witch_craft/witch_spells.

   layout:
     /var/witch_craft/witch_spells:
       bind: $SNAP/witch_spells

2. Check Confinement Settings: If using strict confinement, verify that the snap has the necessary permissions or consider using classic confinement if feasible.

3. Add Post-Install Hook (if applicable): If Snapcraft configuration alone does not resolve the issue, consider adding a post-install hook to manually copy witch_spells to the desired location on the host.