test: establish independent verification workflow

[danielFlemstrom]

Summary

• Establishes the independent verification workflow for Curbpack.
• Adds frozen verification-run setup, controlled repository states, verification procedures, test suites, and executable EV cases.
• Aligns the reference-product integration and R-state handling.

Why

• Make verification reproducible against a frozen Curbpack commit and reference-product commit.
• Make test cases independently executable from known repository states.
• Separate repository state, pack input, and execution configuration.

Test plan

• go test ./...
• make start-verification-run
• EV-001 executed successfully against the frozen reference product

Ops checklist (required)

• Branch is up to date with main before merge
• Required CI checks are green
• No direct push to main (PR merge only)
• Confirm Pages deploy if site content changed

Repository policy

• Product change targets RI-SE/curbpack (not afelin-only)
• This is not a full-tree parity/mirror/sync PR
• Fork-specific maintainer docs unchanged or intentionally scoped

Risk / rollback

• Rollback path is clear (revert PR)

[github-actions]

Curbpack check

✅ Gates green — readiness 100%

Prepares evidence for human review — not a conformity assessment or certification.