The library_paths method was using readlines which could leave file
descriptors open due to Ruby's garbage collection behavior. When
processing many packages during 'brew upgrade' or 'brew linkage',
this caused "Too many open files" errors on Linux systems.
Changes:
- Replace readlines with explicit file.open block to ensure proper closure
- Add caching to avoid repeatedly reading /etc/ld.so.conf during a session
- Cache included files as well to optimize recursive include processing
Fixes: #19866, #20302, #19177, #20223🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
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