the strictly confined jhack snap makes use of a personal-files interface to read/write
~/.local/share/juju, so that the juju client it embeds can share the controllers, models, credentials, etc… available to the user-owned juju snap.
Read access via
juju-client-observe is not enough, because the embedded juju client needs to create certain lock files.
~/.local/share/juju to a snap-owned location (to gain write access) means that any newly added controllers, any credentials change, any changes to the local state essentially (current model, etc…) would desync the two jujus.
So the only way is to share r/w access to that directory.
Thanks in advance! Pietro