feat(safety): add geriatric deprescribing checker

[cursor]

Summary

• Add GeriatricDeprescribingChecker for age≥65 deprescribing review opportunities (PPI/Z-drug/antihistamine/NSAID mini-catalog)
• Complements Beers + STOPP/START without duplicating their formal criteria
• Unit tests, SAFETY/README/CHANGELOG docs, demo GIF

Motivation

Gap vs clinical decision-support demos (OpenCDS-style deprescribing panels): Beers/STOPP flag PIMs/omissions, but portfolios also need an explicit deprescribing-opportunity checker for agent demos with GPT-5.5 / Claude Sonnet 4.6 / Gemini 3.x / Kimi K2.

Changes

• Feature / fix
• Tests added or updated
• Documentation updated
• CHANGELOG updated

Test Plan

pip install -e ".[dev]"
ruff check src tests && ruff format --check src tests
mypy src
pytest tests/unit/safety/test_geriatric_deprescribing_checker.py -q

Suggested repo metadata

• Description: Medical agent core with safety checkers, FHIR-minded workflows, and GPT-5.5 / Claude Sonnet 4.6 / Gemini 3.x / Kimi K2 routing
• Topics: medical-ai, deprescribing, clinical-safety, fhir, llm-agents, python

Checklist

• Self-reviewed the diff
• No secrets committed
• CI passes

RESEARCH USE ONLY — educational demo catalog, not clinical advice.