Replace YAML customization with a three-layer TOML override model (skill
defaults → team overrides → personal preferences). Each skill now ships a
customize.toml with its full customization surface and a
resolve-customization.py script that merges layers just-in-time during
activation. Personal .user.toml files are gitignored; team .toml files
are committed.
Updates all 7 agent skills and product-brief workflow with new activation
steps, customization defaults, and merge scripts. Rewrites the
customize-bmad how-to guide for the new system.
Brian Madison