test: repair stale pending-action and bundle standalone smokes

[chubes4]

Problem

Three standalone smoke paths fail on current origin/main (271a9ff5f) before candidate changes are applied:

• php tests/signed-pending-action-resolution-smoke.php reaches the second acceptance and then treats the canonical WP_Error result as an array at line 397.
• php tests/agent-bundle-upgrade-planner-smoke.php reaches pending-action resolution with incomplete standalone option/fence plumbing; depending on bootstrap order it either lacks add_option() or later treats the canonical WP_Error result as an array.
• php tests/agent-bundle-portable-update-smoke.php reports five stale assertions: two existing-flow normalization assertions and three package CLI source-string assertions.

These failures reproduced from a clean git archive origin/main with the locked Composer dependency tree. They are not introduced by #3317, but they prevent those broad smokes from serving as candidate gates.

Expected

• Standalone pending-action smokes provide the current durable/transient fence stubs and assert canonical WP_Error failures.
• Portable-update assertions follow current bundle normalization and CLI ownership, or move to behavioral coverage instead of stale source strings.
• Each command exits successfully on main and fails only for a real regression.