Add tests/test_deb_build.sh with four phases:
1. Build .deb packages via dpkg-buildpackage
2. Verify all three packages contain expected files (binaries, man
pages, shared library, headers, pkg-config)
3. Install packages and resolve dependencies
4. Smoke-test installed binaries, ldconfig, and headers
Add a Linux-only CI step in build.yml to run the test.
Statically link the bundled submodule libraries (libcork, libipset,
libbloom) into all targets instead of building them as shared libs.
These are vendored code built from git submodules, not system
libraries, so static linking is correct and eliminates
dpkg-shlibdeps warnings about missing .so files.
Pass -DWITH_STATIC=OFF in debian/rules since debian build-depends
only provide shared library dev packages.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
