security: add CI security scanning and purge compromised trivy-action

[fas89]

Summary

Hardens forge-cli's security posture and purges a supply-chain-compromised GitHub Action the CLI was shipping to its own users.

fluid generate ci emitted aquasecurity/trivy-action — compromised in March 2026 (CVE-2026-33634 / GHSA-69fq-xp46-6x23) — into every generated downstream pipeline. It is replaced with OSV-Scanner across all five CI-system generators. forge-cli's own CI/CD then gains layered, pinned scanning.

What's added

SAST

• .semgrep/fluid-rules.yml — 3 custom rules encoding CLAUDE.md invariants (deleted-module imports, SQL-safety helper bypass, copilot workspace_root confinement), gated in the existing security job. CodeQL is already provided by the repo's default setup — no workflow added here.

Supply chain

• dependency-review job — blocks PRs adding vulnerable / disallowed-licence deps.
• release.yml — Grype container scan (--fail-on high --only-fixed) before the GHCR push, plus a CycloneDX SBOM attached to every release.
• scorecard.yml — weekly OpenSSF Scorecard.

Agentic layer

• tests/cli/test_agentic_redteam.py — 35 deterministic, zero-token adversarial tests pinning the copilot's injection-redaction / workspace-confinement / typed-error defenses; new redteam pytest marker.

Docker

• Upgrade pip/setuptools/wheel in the base image — clears 3 fixable HIGH CVEs the new Grype gate flagged.

Every scanner is pinned by commit SHA or version+checksum. No third-party scanner Actions run in forge-cli's own CI.

Test plan

Verified locally before opening:

• actionlint clean on all workflows
• Semgrep — rules validate; gate scan 0 findings on the repo; all 3 rules confirmed firing on synthetic violations
• bandit security scan passes
• 1583 tests pass (tests/forge/, tests/cli/, generators, test_security.py); full suite (12,231) collects clean
• release.yml Grype gate — built the prod image; grype --fail-on high --only-fixed exits 0 (3 fixable CVEs patched, 37 unfixable base-OS CVEs correctly excluded)
• CycloneDX SBOM generation — valid CycloneDX 1.6
• check_pinned_actions.py exit 0 — every action SHA-pinned
• Security review of the diff — no HIGH/MEDIUM findings

Follow-ups (settings — for a maintainer, not code)

• Settings -> Code security: enable secret scanning + push protection, and private vulnerability reporting.
• After merge: add a main ruleset requiring Security Scan and Dependency Review as status checks.

[github-actions]

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[github-actions]

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[github-advanced-security]

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