ci(security): run gitleaks binary + audit prod deps only

The container-mode runner has no Docker socket, so the gitleaks 'docker run'
step failed; download and run the binary instead. Scope npm audit to production
dependencies (--omit=dev) so dev-toolchain advisories don't block merges, and
match dotnet's own vulnerable-packages line to avoid severity-word false hits.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitea/workflows/security.yml

@@ -17,9 +17,13 @@ jobs:
         with:
           fetch-depth: 0            # full history so gitleaks scans every commit
       - name: Secret scan (gitleaks)
+        # Run the binary directly — the container-mode runner has no Docker socket,
+        # so `docker run` isn't available inside a job.
         run: |
-          docker run --rm -v "$PWD:/repo" zricethezav/gitleaks:latest \
-            detect --source=/repo --redact --verbose --exit-code 1
+          GITLEAKS_VERSION=8.18.4
+          curl -sSL "https://github.com/gitleaks/gitleaks/releases/download/v${GITLEAKS_VERSION}/gitleaks_${GITLEAKS_VERSION}_linux_x64.tar.gz" -o /tmp/gitleaks.tar.gz
+          tar -xzf /tmp/gitleaks.tar.gz -C /tmp gitleaks
+          /tmp/gitleaks detect --source=. --redact --verbose --exit-code=1
 
   dependencies:
     runs-on: ubuntu-latest
@@ -31,9 +35,11 @@ jobs:
       - name: Restore
         run: dotnet restore InboxIntel.sln
       - name: .NET vulnerable packages (fail on any)
+        # Match dotnet's own "has the following vulnerable packages" line rather
+        # than raw severity words, so package/project names can't false-positive.
         run: |
           dotnet list InboxIntel.sln package --vulnerable --include-transitive 2>&1 | tee vuln.txt
-          if grep -qiE 'Critical|High|Moderate|Low' vuln.txt; then
+          if grep -q "has the following vulnerable" vuln.txt; then
             echo "::error::Vulnerable NuGet packages detected — see the table above."
             exit 1
           fi
@@ -41,6 +47,8 @@ jobs:
       - uses: actions/setup-node@v4
         with:
           node-version: '20'
-      - name: npm audit (fail on high/critical)
+      - name: npm audit (production deps, fail on high/critical)
+        # Only production dependencies ship to users; dev-only toolchain advisories
+        # (Vite/PostCSS/etc.) shouldn't block a merge.
         working-directory: frontend
-        run: npm audit --audit-level=high
+        run: npm audit --omit=dev --audit-level=high