ci: minimize stale enforcement comments on pr reopen (#7365)

When the `require_issue_link` workflow closes a PR and posts an
enforcement comment, that comment was never cleaned up after the
situation resolved — leaving a stale "automatically closed" message
visible on reopened PRs. Now all three resolution paths (maintainer
bypass, author fixing the issue link, and contributor assignment)
minimize the enforcement comment as outdated via GraphQL. The cleanup is
best-effort: failures log a warning but never block the primary workflow
logic (label removal, bypass, reopen).

.github/workflows/reopen_on_assignment.yml

@@ -135,4 +135,27 @@ jobs:
               } catch (e) {
                 if (e.status !== 404) throw e;
               }
+
+              // Minimize stale enforcement comment (best-effort;
+              // sync w/ require_issue_link.yml minimize blocks)
+              try {
+                const marker = '<!-- require-issue-link -->';
+                const comments = await github.paginate(
+                  github.rest.issues.listComments,
+                  { owner, repo, issue_number: prNumber, per_page: 100 },
+                );
+                const stale = comments.find(c => c.body && c.body.includes(marker));
+                if (stale) {
+                  await github.graphql(`
+                    mutation($id: ID!) {
+                      minimizeComment(input: {subjectId: $id, classifier: OUTDATED}) {
+                        minimizedComment { isMinimized }
+                      }
+                    }
+                  `, { id: stale.node_id });
+                  console.log(`Minimized stale enforcement comment ${stale.id} as outdated`);
+                }
+              } catch (e) {
+                core.warning(`Could not minimize stale comment on PR #${prNumber}: ${e.message}`);
+              }
             }