Create gem for FileBody class and monkey-patch
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## Phase 1: Research and Gem Creation
- Review and understand the existing MR gitlab!128869 implementation
- Research GitLab gem structure and requirements
- Determine the best architectural approach based on maintainer feedback
- Create the gem structure with the FileBody class and monkey-patch
- Address architectural concerns about where components should live
This is weight 3 because we don't do this kind of work all the time, there will be a learning curve, and the amount of existing context to take in is significant.
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