Backend job had static checks (ruff/mypy) and a dependency-vulnerability
gate but no secret scan; frontend had a dependency audit but no secret
scan either. Adds trufflehog once, on the backend job's full checkout,
covering the whole repository - the last gap for this repo to count as
fully-authored.
Backend CI had ruff/mypy static checks and a real pip-audit-equivalent
was missing; frontend already had npm audit, so backend was the only
side of this repo without any dependency-vulnerability gate (partial
coverage). Adds trivy-action fs scoped to backend/, HIGH/CRITICAL only,
consistent with this security programme's gate convention elsewhere.
Verified clean (0 HIGH/CRITICAL) against backend/pyproject.toml before
wiring in, so the gate does not immediately fail CI.
NuklearRabbit