fix: load .env in production systemd service for chat API keys

- Add EnvironmentFile=/home/txeo/Git/yo/cv/.env to systemd unit
- Add production overrides (GO_ENV, BEHIND_PROXY, ALLOWED_ORIGINS)
- Deploy workflow now auto-updates systemd service file on each deploy

.github/workflows/deploy.yml

@@ -70,6 +70,11 @@ jobs:
             #   git stash pop || echo "⚠️  Could not reapply stash (conflicts?)"
             # fi
 
+            # Update systemd service file if changed
+            echo "📋 Updating systemd service..."
+            sudo cp config/systemd/cv.service /etc/systemd/system/$SERVICE_NAME.service
+            sudo systemctl daemon-reload
+
             echo "🔄 Restarting service..."
             sudo systemctl restart $SERVICE_NAME