feat: improve agent precision and formatting rules

fix 3 layer memory ststem

fix: tell model ~ paths work and warn against root='/' in find_files

fix: expand ~ in fs tools, accept absolute glob patterns, add find_files

feat: enhance LLM formatting capabilities and improve logging in various components

review: ship all 15 quick-win fixes from REVIEW.md via TDD

feat: add youtube_frame_at tool, improve vision URL validation, silence observability logs, and update caveman mode configuration.

feat: implement web search and file processing tools with robust retrieval fallbacks