Make release guards consume the Continuum release profile

[flyingrobots]

Why this matters

.continuum/release.yml now records repo-specific release facts, but the existing release guard still duplicates several of those facts in shell arrays and hardcoded commands. That leaves a drift path between the release profile and executable release law.

Evidence

• .continuum/release.yml declares version sources, docs signposts, validation commands, registries, and workflows.
• scripts/release-guard.sh still hardcodes required release docs and version lockstep paths.
• scripts/check-docs-topology.sh still hardcodes the docs topology.

Done when

• Release guards parse .continuum/release.yml for profile-owned facts.
• Hardcoded release-doc and version-source lists are removed or reduced to schema validation.
• Tests prove the guard fails when the profile drifts from repo state.
• The human runbook remains policy; repo mechanics live in the profile.