1.2.9
Fix sentence case for all remaining ObsidianReviewBot issues:
- Lowercase placeholders (xxxx-xxxx-xxxx-xxxx, sk-ant-..., sk-...)
- Fix GPT model names to use proper acronym format (GPT-4o-mini, GPT-4o, GPT-4-turbo)
- Retain Anthropic and OpenAI brand name labels