fix(root-package-loader): un-ignore 4 tests by fixing stability-flag isset() port

extract_stability_flags ported PHP's `isset($stabilityFlags[$name]) &&
$stabilityFlags[$name] > $stability` as `unwrap_or(i64::MAX) > stability`,
so the check always short-circuited to "already more unstable" and no flag
(e.g. from an explicit `*@dev` requirement) was ever recorded. Fixed using
Option::is_some_and, a direct translation of PHP's isset() && ... check.

Also fixes tests/common/test_case.rs's shared installation_manager()
helper, which built a real InstallationManager::new instead of the
__new_mock constructor (mirroring PHP's FactoryMock::createInstallationManager()),
so it always had zero installers registered and wrote install-path: null
into fixture installed.json files.

Un-ignores test_reinstall_command, test_locally_modified_packages_from_source/
_from_dist, and test_package_still_present_error_when_no_install_flag_used —
the first three were already passing (their #[ignore] reasons were stale),
the last is fixed by the test_case.rs change above.

Updates the #[ignore] reasons on installer_test.rs's three fixture-driven
integration tests to reflect their current state: the install pipeline now
runs end-to-end, but the ~189-fixture installer/ set still hits several
independent, unrelated bugs/gaps that need case-by-case triage rather than
a single fix.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

0 files changed, 0 insertions, 0 deletions