Address review feedback (P3): The User-Installed Skills block was duplicated verbatim in two if/else branches in both buildCategorySkillsDelegationGuide() and Atlas buildSkillsSection(). Extract shared formatCustomSkillsBlock() with configurable header level (#### vs **) so both builders reference a single source of truth.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Atlas had its own buildSkillsSection() in atlas/utils.ts that rendered all skills in a flat table without distinguishing built-in from user-installed. Apply the same HIGH PRIORITY emphasis and CRITICAL warning pattern used in the shared prompt builder.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Split monolithic atlas.ts into modular structure: index.ts (routing), default.ts (Claude-optimized), gpt.ts (GPT-optimized), utils.ts (shared utilities). Atlas now routes to appropriate prompt based on model type instead of overriding model settings.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
