feat: crawler finds a page with two H1 headings and stores the issue (tracer)

- golem15_seo_crawls, crawl pages, links, issues and ignores (P33-37)
- classes/crawl: fetchguard client on the site host and its www twin,
  sitemap index and robots.txt seeds, two workers with a delay, limits
- h1_missing and h1_multiple with the P33-38 fix route
- POST /_seo/api/v1/crawls queues the golem15.seo.crawl job; GET /issues
  answers the stored issues with id, severity, source, fix, found_at,
  ignored and crawl_id

classes/issues.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"git.golem15.com/golem15/sm-seo-plugin/models"
+	"gorm.io/gorm"
 )
 
 // The kinds of the CMS-data issue report (D-13, D-14 CMS part). The
@@ -309,3 +310,11 @@ func (s *Service) canonicalProblem(ctx context.Context, canonical string) (kind,
 	}
 	return IssueCanonicalNoindex, "", nil
 }
+
+// Actor names who runs an audit operation (a crawl start, a cancel, an
+// ignore): the backend administrator's id and name, and whether the call
+// came through MCP.
+func (s *Service) Actor(ctx context.Context, db *gorm.DB) (id *uint, name string, mcp bool) {
+	id, name = s.author(ctx, db, models.ViaAdmin)
+	return id, name, ViaOf(ctx) == models.ViaMCP
+}