* Add CodeUp CI integration (issue #517)
Adds examples/codeup_ci with:
- post_review.py: runs ocr review --format json and posts a
GLOBAL_COMMENT summary via CodeUp's CreateChangeRequestComment API
- post_review_test.py: unit tests (27 passing)
- codeup-flow.yml: example Yunxiao Flow pipeline
- README.md: setup docs and known limitations (v1 = summary
comment only, inline comments as a follow-up)
* chore: ignore Python cache files
* Add actual file contents for CodeUp CI integration
* Use generic placeholder for OCR_LLM_MODEL example
* Address review: remove local .gitignore, add trailing newlines, simplify testing docs
