Hivemind delegates grunt work to headless opencode workers (scout/coder/tester)
while the orchestrating agent stays the planner, reviewer, and merger.
- placed under engineering/ per repo layout; targets dev per CONTRIBUTING
- frontmatter is name + description only; SKILL.md is 165 lines
- anti-patterns and cross-references sections included
- external opencode CLI dependency and free-model caveats documented up front
- runtime state (.runs/) gitignored, not committed
