ci: add security scanning and SBOM to release pipeline

- ci.yml: add security job (gitleaks, cargo-audit, cargo-deny, trivy fs)
- release.yml: restructure into build-binary + build-docker matrix + release
  - build binary once on self-hosted, reuse across all Docker builds
  - trivy image scan per matrix variant, results to GitHub Security tab
  - SBOM generation in SPDX and CycloneDX formats attached to release
- deny.toml: cargo-deny policy (allowed licenses, banned openssl, crates.io only)
- Dockerfile: remove Rust build stage, use pre-built binary
- Dockerfile.astra, Dockerfile.redos: FROM scratch for Russian certified OS support

.github/workflows/ci.yml

@@ -27,3 +27,59 @@ jobs:
 
       - name: Run tests
         run: cargo test --package nora-registry
+
+  security:
+    name: Security
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      security-events: write  # for uploading SARIF to GitHub Security tab
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0  # full history required for gitleaks
+
+      - name: Install Rust
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Cache cargo
+        uses: Swatinem/rust-cache@v2
+
+      # ── Secrets ────────────────────────────────────────────────────────────
+      - name: Gitleaks — scan for hardcoded secrets
+        uses: gitleaks/gitleaks-action@v2
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      # ── CVE in Rust dependencies ────────────────────────────────────────────
+      - name: Install cargo-audit
+        run: cargo install cargo-audit --locked
+
+      - name: cargo audit — RustSec advisory database
+        run: cargo audit
+
+      # ── Licenses, banned crates, supply chain policy ────────────────────────
+      - name: cargo deny — licenses and banned crates
+        uses: EmbarkStudios/cargo-deny-action@v2
+        with:
+          command: check
+          arguments: --all-features
+
+      # ── CVE scan of source tree and Cargo.lock ──────────────────────────────
+      - name: Trivy — filesystem scan (Cargo.lock + source)
+        uses: aquasecurity/trivy-action@master
+        with:
+          scan-type: fs
+          scan-ref: .
+          format: sarif
+          output: trivy-fs.sarif
+          severity: HIGH,CRITICAL
+          exit-code: 0  # warn only; change to 1 to block the pipeline
+
+      - name: Upload Trivy fs results to GitHub Security tab
+        uses: github/codeql-action/upload-sarif@v3
+        if: always()
+        with:
+          sarif_file: trivy-fs.sarif
+          category: trivy-fs