CLEANUP: Remove temporary analysis markdown files

The NORMALIZATION_ISSUES_ANALYSIS.md and SCHEMA_INTEGRITY_ANALYSIS_REPORT.md
files were temporary analysis artifacts that served their purpose. The actual
improvements have been implemented in the schemas and Python models.

Keeping the useful tools:
- fk_analysis.py (foreign key analysis tool)
- generated_models.py (Python models for all entities)

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: pwt-cd