Fixes
- Ignore undefined objects in link annotation logic (fixes #191).
- Flatten indirect references in imported annotation dictionaries (fixes #195).
Tweaks
- Ensure newline before endobj token (fixes #184).
- Optimized fallback logic in flate decode method.
- Added tests for PHP 8.3.
Features
- Added PdfType::flatten() method, which flattens indirect objects to direct objects.