The dry-run failed with HTTP 403 on the branches API: PACKAGE_TOKEN is a
package-scoped token (registry push/delete) and can't read repo branches. Split
by capability: branch reads now use the automatic Actions token (github.token,
repo read via 'permissions: contents: read'); package list + delete keep
PACKAGE_TOKEN. Also replaced the bare 'curl -f' failures with a get() helper that
reports the HTTP code + a token-scope hint, so an auth problem can't look like
'no results' (which would otherwise skew the reconcile).