Require explicit instructions config for all muse agents
Change default instruction configuration from implicit to explicit opt-in:
- system: "journal" → None (empty string if not specified)
- facets: true → false
- sources.audio/screen: true → false
This ensures every agent explicitly declares what instructions it needs
rather than relying on hidden defaults. Generators must now specify their
sources, and tool agents must opt-in to system prompts and facet context.
Updated 14 muse prompt files to preserve their existing behavior by adding
explicit instructions configs. Utility prompts (occurrence.md, anticipation.md)
intentionally left without instructions as they don't use the system.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>