feat(release): build verified full-registry catalog candidates

tools/release/govoplan_release/version_alignment.py

@@ -10,6 +10,7 @@ import subprocess
 import tomllib
 
 from .git_state import collect_versions, sanitized_git_environment
+from .registry_reference import registry_artifact_conflicts, registry_entry_source
 from .workspace import load_repository_specs, resolve_repo_path
 
 
@@ -407,6 +408,11 @@ def candidate_catalog_version_issues(payload: object) -> tuple[VersionAlignmentI
             )
 
     release = payload.get("release")
+    registry_entries = [core_release, *(modules if isinstance(modules, list) else [])]
+    issues.extend(
+        _catalog_shape_issue("artifact_integrity", issue)
+        for issue in registry_artifact_conflicts(registry_entries)
+    )
     if isinstance(release, dict):
         issues.extend(_catalog_release_issues(release, represented=represented))
     return tuple(issues)
@@ -419,6 +425,15 @@ def _catalog_entry_issues(
     represented: dict[str, str],
 ) -> list[VersionAlignmentIssue]:
     issues: list[VersionAlignmentIssue] = []
+    try:
+        registry_source = registry_entry_source(entry)
+    except ValueError as exc:
+        return [_catalog_shape_issue(source, str(exc))]
+    if registry_source is not None:
+        previous = represented.setdefault(registry_source.repository, registry_source.version)
+        if previous != registry_source.version:
+            issues.append(_catalog_shape_issue(source, "repository appears with conflicting catalog versions"))
+        return issues
     version = entry.get("version")
     normalized_version = version.removeprefix("v") if isinstance(version, str) and version else None
     if normalized_version is None: