- apk: Info test uses busybox (pre-installed) instead of curl (not installed)
- apk: LatestVersion test uses tree (installed during test)
- dpkg: Owner test uses /usr/bin/bash (not /bin/bash symlink)
- flatpak: List test checks both Name and Application ID fields
- dnf: pin Fedora to 41 (dnf4); dnf5 has incompatible output format
Type assertions require an interface type, not a concrete struct pointer.
Changed all integration tests from 'mgr := pkg.New()' to
'var mgr snack.Manager = pkg.New()' so capability checks like
mgr.(snack.VersionQuerier) compile correctly.