docs: ✏️ Enhance content with coding tips, mental models, and public speaking insights
Added a "Coding Tips" section in Large Language Models.md for effective model guidance. Expanded Mental Models.md with detailed sections on mental models that influence reality, knowledge, systems, and more. Updated Problem Solving.md with a note on addressing social issues collaboratively. Improved Public Speaking.md with tips for crafting compelling proposals. These enhancements aim to provide nuanced and actionable insights across documents.