feat: add copier template for governance distribution

[FScholPer]

Scope

This PR adds the Copier-based distribution layer for the governance overlay.

Why

Extracted from oversized PR #51 to separate distribution mechanics from governance-core review.

Dependency

• merge after feat: add SCORE governance core contracts #54 and feat: add shared SCORE coding instructions #55

Out of scope

• root governance schemas and manifest
• root docs and hygiene automation

Validation

• one focused branch/commit slice for template distribution

Merge Order

1. feat: add SCORE governance core contracts #54 (core contracts)
2. feat: add shared SCORE coding instructions #55 (instruction pack)
3. feat: add copier template for governance distribution #56 (copier template)
4. chore: add markdown hygiene checks and governance docs #57 (docs and hygiene)

Relationship to original PR

This PR is part of the split of oversized PR #51.

[github-actions]

Thanks for the pull request. This thread has been quiet for 30 days, so we are marking it as stale for now. Please take a quick look and let us know whether it is still up to date, still relevant, needs review, or is ready to merge. Any new activity will remove the stale label automatically. If nothing changes in the next 10 days, we will close it to keep the backlog current.