chore(ci): standardize and update CI workflows for compatibility and consistency
- Updated action versions (`checkout@v4`, `upload-artifact@v4`, `download-artifact@v4`) for enhanced compatibility and security
- Removed unsecure Node.js version allowance to align with *-latest OS requirements
- Migrated test demos to `rehldsorg/testdemos:latest` container with a streamlined testing approach via matrix strategy and `runTest.sh`
- Standardized Linux dependency installation for consistent build environment across jobs
- Unified CI workflow structure with `rehlds` and `regamedll` repositories for better consistency
- Optimized artifact deployment steps and removed unnecessary cleanup operations
Co-authored-by: s1lentq <s1lentsk@yandex.ru>
