[renecannao]

Summary

• Add MariaDB 11.8.6 (latest 11.x LTS release, includes Galera wsrep 26.4.25) as a tested environment
• Add CI coverage in all 3 workflow files with full functional testing:
  • Galera topology (replication + data verification) — all_tests.yml, integration_tests.yml
  • ProxySQL + Galera (deploy with ProxySQL, write/read through proxy) — proxysql_integration_tests.yml
• Existing 10.11.16 tests preserved alongside new 11.8.6 coverage
• Legacy OpenSSL 1.0 installation conditionalized (legacy-openssl flag) — 11.x uses system OpenSSL 3.x
• Updated README tested configurations table

Changes

File	Change
.github/workflows/all_tests.yml	Matrix-ize mariadb-galera-test with 10.11.16 + 11.8.6
.github/workflows/integration_tests.yml	Add 11.8.6 to Galera matrix
.github/workflows/proxysql_integration_tests.yml	Matrix-ize proxysql-galera with 10.11.16 + 11.8.6
README.md	Add 11.8 to MariaDB tested versions

Summary by CodeRabbit

• Chores
  • Enhanced CI to run Galera integration tests across MariaDB 10.11 and 11.8, including an optional legacy OpenSSL path.
• Tests
  • Expanded ProxySQL and Galera test coverage with matrix-driven scenarios for multiple Galera versions.
• Documentation
  • Updated tested configurations to list MariaDB 10.11 and 11.8.
• Bug Fixes
  • Improved startup diagnostics to detect and report server error log failures during sandbox startup.