fix(release): preserve the monotonic sequence ledger

[rldyourmnd]

Summary

• require an explicit monotonic release_sequence workflow input
• stop deriving trust order from repository-local github.run_number
• document that repository migration does not reset the consumer acceptance ledger

Root cause

The verified public 0.1.2 canary used sequence 4, while the existing trusted GDS lineage had already accepted sequence 43. Offline verification correctly quarantined it as a rollback.

Verification

• go test ./core/releasebuilder
• actionlint .github/workflows/release-bundle.yml
• scripts/validate_go_core.sh --quick
• git diff --check