Addresses Gitea issue #5 (Agent Rails): Explore/Plan agent types are
read-only but were recommended for tasks that need to write artifacts.
Replaced with write-capability guard in model-tiers.md, steered delegation
to scout/search/researcher. Tightened Athanor metaphor across all skills
— it IS the oven, plans go into it. Fixed assistant skill to route to Igor.
Scaffold .claude/spire/project.md with reliquary-specific facts,
create adept templates at docs/workpad/adepts/, build the Zathras
agent and skill (Spire's self-maintenance coordinator), and wire
/assistant as a local alias for spire:zathras.