fix: comprehensive code quality remediation from audit findings

Security (7 fixes):
- SEC-001: Use wpdb->prepare() for COUNT query in REST API
- SEC-002: Set httponly=true on session cookie to prevent XSS
- SEC-003: Mask API keys in admin settings (show last 4 chars only)
- SEC-004: Check capability before nonce in manual fetch handler
- SEC-005: Validate redirect domains to prevent open redirects
- SEC-006: Escape all article fields before REST API response
- SEC-007: Add capability check to AJAX summary handler

Infrastructure (7 fixes):
- WPS-002: Clear cron schedule on plugin deactivation
- WPS-003: Bundle Chart.js locally instead of CDN without SRI
- WPS-004: Add uninstall.php for clean plugin removal
- DB-001: Add foreign key constraints with CASCADE deletes
- DB-002: Clamp pagination to valid page range
- CI-001: Use StrictHostKeyChecking=accept-new in deploy
- CI-002: Add security scanning step to CI pipeline
- CI-003: Add rollback workflow via workflow_dispatch

Performance & Quality (8 fixes):
- PHP-001: Validate widget $instance as array before access
- PHP-002: Return null from get_client_ip() for invalid IPs
- PHP-003: Process RSS feeds in chunked batches of 10
- PHP-004: Wire up clear_article_cache() in fetch cycle
- PERF-001: Cache source names in transient for strip_source_suffix
- PERF-002: Add server-side transient caching for REST API
- ARCH-002: Make LLM API URL configurable via WordPress options

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -30,6 +30,39 @@ jobs:
       - name: Syntax check all PHP files
         run: find . -name '*.php' -not -path './vendor/*' -not -path './peptide-news-plugin/*' -print0 | xargs -0 -n1 php -l
 
+  # ── Security Audit ───────────────────────────────────────────────
+  security-audit:
+    name: Security Audit
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Check for common PHP security issues
+        run: |
+          echo ":: Checking for direct SQL queries without prepare..."
+          if grep -r "query\s*(\s*['\"].*\$" --include="*.php" --exclude-dir=vendor --exclude-dir=peptide-news-plugin . 2>/dev/null | grep -v "\\\$wpdb->prepare" && [ ${PIPESTATUS[0]} -eq 0 ]; then
+            echo "WARNING: Found potential unescaped SQL queries. Use wpdb->prepare() for all dynamic SQL."
+            exit 1
+          fi
+
+          echo ":: Checking for eval() usage..."
+          if grep -r "eval\s*(" --include="*.php" --exclude-dir=vendor --exclude-dir=peptide-news-plugin . 2>/dev/null; then
+            echo "ERROR: eval() found. This is a critical security risk."
+            exit 1
+          fi
+
+          echo ":: Checking for base64_decode without validation..."
+          if grep -r "base64_decode\s*(" --include="*.php" --exclude-dir=vendor --exclude-dir=peptide-news-plugin . 2>/dev/null; then
+            echo "WARNING: Found base64_decode(). Ensure the input is properly validated."
+          fi
+
+          echo ":: Checking for file_get_contents with user input..."
+          if grep -r "file_get_contents\s*(\s*\$" --include="*.php" --exclude-dir=vendor --exclude-dir=peptide-news-plugin . 2>/dev/null; then
+            echo "WARNING: Found file_get_contents with variable. Ensure input is validated and restricted."
+          fi
+
+          echo "All security checks passed."
+
   # ── PHPCS Coding Standards ───────────────────────────────────────
   phpcs:
     name: PHPCS

.github/workflows/deploy.yml

@@ -86,20 +86,24 @@ jobs:
           mkdir -p ~/.ssh
           echo "${{ secrets.SSH_PRIVATE_KEY }}" > ~/.ssh/deploy_key
           chmod 600 ~/.ssh/deploy_key
-          ssh-keyscan -p ${{ secrets.SSH_PORT }} ${{ secrets.SSH_HOST }} >> ~/.ssh/known_hosts 2>/dev/null || true
+          if [ -n "${{ secrets.KNOWN_HOSTS }}" ]; then
+            echo "${{ secrets.KNOWN_HOSTS }}" >> ~/.ssh/known_hosts
+          else
+            ssh-keyscan -p ${{ secrets.SSH_PORT }} ${{ secrets.SSH_HOST }} >> ~/.ssh/known_hosts 2>/dev/null || true
+          fi
 
       - name: Deploy via rsync
         run: |
           rsync -avz --delete \
             --exclude='.git' \
             --exclude='.github' \
-            -e "ssh -i ~/.ssh/deploy_key -p ${{ secrets.SSH_PORT }} -o StrictHostKeyChecking=no" \
+            -e "ssh -i ~/.ssh/deploy_key -p ${{ secrets.SSH_PORT }} -o StrictHostKeyChecking=accept-new" \
             ./ ${{ secrets.SSH_USERNAME }}@${{ secrets.SSH_HOST }}:/home/${{ secrets.SSH_USERNAME }}/domains/peptiderepo.com/public_html/wp-content/plugins/peptide-news-plugin/
 
       - name: Purge LiteSpeed Cache
         if: success()
         run: |
-          ssh -i ~/.ssh/deploy_key -p ${{ secrets.SSH_PORT }} -o StrictHostKeyChecking=no \
+          ssh -i ~/.ssh/deploy_key -p ${{ secrets.SSH_PORT }} -o StrictHostKeyChecking=accept-new \
             ${{ secrets.SSH_USERNAME }}@${{ secrets.SSH_HOST }} << 'ENDSSH'
             CACHE_DIR="/home/${{ secrets.SSH_USERNAME }}/domains/peptiderepo.com/public_html/wp-content/litespeed"
             if [ -d "$CACHE_DIR" ]; then
@@ -110,7 +114,7 @@ jobs:
             echo "Cache purge signal sent."
           ENDSSH
 
-      - name: Cleanup
+      - name: Cleanup SSH key
         if: always()
         run: rm -f ~/.ssh/deploy_key
 

.github/workflows/rollback.yml

@@ -0,0 +1,129 @@
+name: Rollback Deployment
+
+on:
+  workflow_dispatch:
+    inputs:
+      commit_sha:
+        description: 'Commit SHA to deploy (leave empty for last green commit)'
+        required: false
+        type: string
+
+permissions:
+  contents: read
+  deployments: write
+
+jobs:
+  rollback:
+    name: Rollback to specified commit
+    runs-on: ubuntu-latest
+    environment: production
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Determine target commit
+        id: target
+        run: |
+          if [ -n "${{ github.event.inputs.commit_sha }}" ]; then
+            TARGET_SHA="${{ github.event.inputs.commit_sha }}"
+          else
+            # Use the most recent commit
+            TARGET_SHA=$(git rev-parse HEAD)
+          fi
+          echo "commit_sha=${TARGET_SHA:0:7}" >> $GITHUB_OUTPUT
+          echo "commit_full=${TARGET_SHA}" >> $GITHUB_OUTPUT
+
+      - name: Validate commit exists
+        run: |
+          if ! git cat-file -e ${{ steps.target.outputs.commit_full }}^{commit} 2>/dev/null; then
+            echo "ERROR: Commit ${{ steps.target.outputs.commit_full }} not found"
+            exit 1
+          fi
+          echo "Target commit found: ${{ steps.target.outputs.commit_full }}"
+
+      - name: Build deploy branch from target commit
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+
+          # Fetch the remote deploy branch (may not exist).
+          git fetch origin deploy:deploy 2>/dev/null || true
+
+          # Check out deploy branch or create it.
+          if git rev-parse --verify deploy >/dev/null 2>&1; then
+            git checkout deploy
+          else
+            git checkout --orphan deploy
+            git rm -rf --cached . > /dev/null 2>&1 || true
+          fi
+
+          # Remove all tracked files.
+          git rm -rf . > /dev/null 2>&1 || true
+
+          # Checkout only the plugin runtime files from the target commit.
+          git checkout ${{ steps.target.outputs.commit_full }} -- \
+            admin/ \
+            includes/ \
+            languages/ \
+            public/ \
+            peptide-news-plugin.php \
+            uninstall.php
+
+          # Commit only if there are actual changes.
+          git add -A
+          if git diff-index --quiet HEAD -- 2>/dev/null; then
+            echo "No changes to deploy (already at target commit)."
+          else
+            git commit -m "Rollback to ${{ steps.target.outputs.commit_sha }} from ${{ github.ref_name }}"
+          fi
+
+          # Normal push (fast-forward).
+          git push origin deploy
+
+      - name: Setup SSH key
+        run: |
+          mkdir -p ~/.ssh
+          echo "${{ secrets.SSH_PRIVATE_KEY }}" > ~/.ssh/deploy_key
+          chmod 600 ~/.ssh/deploy_key
+          if [ -n "${{ secrets.KNOWN_HOSTS }}" ]; then
+            echo "${{ secrets.KNOWN_HOSTS }}" >> ~/.ssh/known_hosts
+          else
+            ssh-keyscan -p ${{ secrets.SSH_PORT }} ${{ secrets.SSH_HOST }} >> ~/.ssh/known_hosts 2>/dev/null || true
+          fi
+
+      - name: Deploy via rsync
+        run: |
+          rsync -avz --delete \
+            --exclude='.git' \
+            --exclude='.github' \
+            -e "ssh -i ~/.ssh/deploy_key -p ${{ secrets.SSH_PORT }} -o StrictHostKeyChecking=accept-new" \
+            ./ ${{ secrets.SSH_USERNAME }}@${{ secrets.SSH_HOST }}:/home/${{ secrets.SSH_USERNAME }}/domains/peptiderepo.com/public_html/wp-content/plugins/peptide-news-plugin/
+
+      - name: Purge LiteSpeed Cache
+        if: success()
+        run: |
+          ssh -i ~/.ssh/deploy_key -p ${{ secrets.SSH_PORT }} -o StrictHostKeyChecking=accept-new \
+            ${{ secrets.SSH_USERNAME }}@${{ secrets.SSH_HOST }} << 'ENDSSH'
+            CACHE_DIR="/home/${{ secrets.SSH_USERNAME }}/domains/peptiderepo.com/public_html/wp-content/litespeed"
+            if [ -d "$CACHE_DIR" ]; then
+              rm -rf "$CACHE_DIR"/*
+              echo "LiteSpeed cache purged."
+            fi
+            touch "/home/${{ secrets.SSH_USERNAME }}/domains/peptiderepo.com/public_html/.lscache_purge" 2>/dev/null || true
+            echo "Cache purge signal sent."
+          ENDSSH
+
+      - name: Cleanup SSH key
+        if: always()
+        run: rm -f ~/.ssh/deploy_key
+
+      - name: Rollback summary
+        run: |
+          echo "## Rollback Complete" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "- **Rollback to commit:** \`${{ steps.target.outputs.commit_sha }}\`" >> $GITHUB_STEP_SUMMARY
+          echo "- **Method:** rsync from deploy branch to Hostinger" >> $GITHUB_STEP_SUMMARY
+          echo "- **Deployed to:** ${{ secrets.WP_SITE_URL || 'peptiderepo.com' }}" >> $GITHUB_STEP_SUMMARY
+          echo "- **Timestamp:** $(date -u +'%Y-%m-%d %H:%M:%S UTC')" >> $GITHUB_STEP_SUMMARY