Add three supporting documents for prompt library maintenance:
- PROMPT_LIBRARY_STATUS.md: current health, inventory of all 36
prompts, changes this run, known remaining issues
- STYLE_GUIDE.md: canonical prompt template, naming conventions,
voice/tone guidance, anti-patterns to avoid
- RESEARCH_LOG.md: web research on prompt-engineering best practices
from Anthropic and OpenAI (2025-2026), with library impact analysis
https://claude.ai/code/session_01Nz6FJopPp2YHEscJrRAFNv
