fix: CFFI library paths for CL build — search /tmp/ac-build and /lib64
The SBCL build couldn't find libquickjs.so because CFFI only searched
the default paths. Added explicit paths for build time (/tmp/ac-build)
and runtime (/lib64). Also set LD_LIBRARY_PATH in init script.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>