Issue forms: per-type intake templates + config.yml

[Eiluviann]

Context

Part of Org framework foundations. Structured intake so every issue is well-formed — Definition-of-Ready fields prompted + the always-present DoD checklist. Canonical forms live in template/.github/ISSUE_TEMPLATE/, synced to all repos.

Scope

• 5 per-type issue forms (feature/bug/chore/spike/docs.yml), each pre-setting its type: + Acceptance Criteria + a DoD checkbox block.
• config.yml: blank_issues_enabled: false; route ideas to org Discussions.

Acceptance criteria

• 5 forms + config.yml present in template/.github/ISSUE_TEMPLATE/
• Each form sets its issue type and carries a DoD checklist

Definition of Done

• Merged via PR · ready for sync_scaffold to propagate