Convert docker-compose-prod.yml to Ansible template with vault secrets

- Create docker-compose-prod.yml.j2 with vault variables (db_password, redis_password, meilisearch_master_key)
- Add template deployment step in playbook after stop containers
- Remove docker-compose-prod.yml from git tracking (now generated by Ansible)
- Add docker-compose-prod.yml to .gitignore

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitignore

@@ -14,6 +14,7 @@
 ###< phpunit/phpunit ###
 
 /public/build/
+docker-compose-prod.yml
 node_modules/
 .idea/
 cert/