Validates and configures all dependencies required for the THE BOOK. This is a STANDALONE skill that runs BEFORE plugin workflows begin. It checks for Python, build tools, CMake, JUCE, pluginval, and the thebook CLI command, optionally installing missing dependencies with user approval. Configuration is saved to .claude/system-config.json for use by other skills. Use when user mentions setup, installation, dependencies, missing tools, or when SessionStart hook detects configuration issues.