[Feature] Add/improve BSD build workflows with Lua version selection

[Feature] Add/improve BSD build workflows with Lua version selection

Add comprehensive GitHub Actions workflows for BSD systems with the ability
to select Lua version (LuaJIT, Lua 5.1, 5.3, 5.4).

NetBSD workflow improvements:
- Add Lua version selection (luajit, lua51, lua53, lua54)
- Fix missing dependencies (libarchive, zstd, xxhash, file)
- Remove || true from pkg_add to catch installation failures
- Add -DENABLE_HYPERSCAN=OFF (not available on NetBSD)
- Add -DSYSTEM_ZSTD=ON and -DSYSTEM_XXHASH=ON flags
- Add conditional ENABLE_LUAJIT based on Lua version selection
- Add NetBSD 9.4 to supported versions
- Fix test executable paths (add ./ prefix)

New FreeBSD workflow:
- Support FreeBSD 14.2, 13.4, 13.3
- Lua version selection (luajit, lua51, lua53, lua54)
- Full dependency list including hyperscan
- Enable hyperscan support (-DENABLE_HYPERSCAN=ON)
- Use system zstd and xxhash libraries
- Proper pkg update before installation

New OpenBSD workflow:
- Support OpenBSD 7.6, 7.5, 7.4
- Lua version selection (luajit, lua51, lua53)
- Full dependency list including hyperscan
- Enable hyperscan support
- Disable jemalloc (-DENABLE_JEMALLOC=OFF)
- Use OpenBSD-specific package names (icu4c, perl-5, lua%5.x)
- Use system zstd and xxhash libraries

All workflows:
- Use workflow_dispatch trigger for manual execution
- Allow selection of OS version and Lua version
- Use vmactions VMs for BSD testing
- Run both C++ and Lua unit tests
- Use Ninja build system for faster compilation

This provides comprehensive testing across different BSD platforms and
Lua versions, ensuring Rspamd builds correctly on various configurations.