[sasan1200]

Changes

• vendor/mlx-agent moves from 6e6effd to 856d437 (ci: notify the plugin catalog on release mlx-agent#99, fix: update filelock and setuptools backend locks mlx-agent#100): backend locks pin filelock 4.2.4 and setuptools 84.2.1, clearing the advisories that fail make pip-audit at 5c6c7b7.
• make pip-audit audits every backend lock and fails after the last one instead of stopping at the first failure.
• make pip-audit installs the pip-audit version pinned in requirements.txt (2.7.3) whenever .venv has another version; it previously installed the newest release.
• The make targets reference describes the target.

Verification

• make pip-audit fails at 5c6c7b7 (14 advisories in mflux.lock) and exits 0 at this head, switching .venv from pip-audit 2.10.1 to 2.7.3 and auditing all six locks.
• With the 6e6effd mflux.lock first in BACKEND_LOCKS, make pip-audit reports its 14 advisories, audits the six current locks after it and exits non-zero.
• tests/test_pip_audit_target.py fails on the previous Makefile (the second lock is never audited) and passes at this head.
• make test 251 OK (4 skipped), make docs-test 15 OK, make test-swift 2030 tests with 0 failures (50 skipped).