Update Docker configuration and add Gitea CI/CD workflows

- Change Docker image in docker-compose.prod.yml to use 'portfolio-app:latest'.
- Add new scripts for Gitea deployment and setup of Gitea runner.
- Introduce CI/CD workflows for automated testing, security scanning, and deployment in Gitea.
- Enhance package.json with new deployment scripts for Gitea integration.

package.json

@@ -32,6 +32,8 @@
     "deploy": "./scripts/deploy.sh",
     "auto-deploy": "./scripts/auto-deploy.sh",
     "quick-deploy": "./scripts/quick-deploy.sh",
+    "gitea-deploy": "./scripts/gitea-deploy.sh",
+    "setup-gitea-runner": "./scripts/setup-gitea-runner.sh",
     "monitor": "./scripts/monitor.sh",
     "health": "curl -f http://localhost:3000/api/health"
   },