* docs: add changeset guidelines to contributing docs
Contributors and agents need to know when and how to add changesets.
Without one, changes to published packages won't trigger a release.
- CONTRIBUTING.md: full Changesets section with when/when-not, how to
add, writing descriptions, examples for patch/minor/major
- AGENTS.md: concise changeset subsection using --empty for
non-interactive use, added as step in PR flow
- PR template: changeset checkbox in checklist
* docs: note that multiple changes need separate changesets
* chore: add PR template, issue templates, and contribution policy
Drive-by feature PRs are becoming a problem. This adds guardrails:
- PR template with type selection, checklist, and AI disclosure
- Bug report issue template (structured YAML form)
- Issue config that redirects features to Discussions and disables blank issues
- PR compliance workflow that enforces template completion and requires
a Discussion link for feature PRs
- Contribution policy in CONTRIBUTING.md (acceptance tiers, AI PR rules)
- Agent-facing rules in AGENTS.md (follow the template, no bulk changes)
* fornat
