feat: orphan pages and merged CMS issues with fix routes

- orphan_page for listed indexable pages no crawled page links to, with
  pages mentioning the title or focus keyphrase as suggestions (D-82)
- CMS-data image_alt and h1_in_content from the content descriptors
  (TopHeading 2 only), stored with the crawl as source cms (D-85, D-50)
- seo-page names Tools edit seo_update_page; every stored issue carries
  a tool or fix code with details.what (P33-38)
- TestIssueMerge (ignored fingerprints survive the next crawl, fixed
  pages lose their issues) and TestStagingCrawl (Pitfall 12)

classes/issues.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"git.golem15.com/golem15/sm-seo-plugin/models"
+	"git.golem15.com/golem15/summercms/modules/pact"
 	"gorm.io/gorm"
 )
 
@@ -26,6 +27,13 @@ const (
 	// keeps Googlebot from (D-24): an error, since the sitemap asks for a
 	// page the crawler may not fetch.
 	IssueSitemapBlocked = "sitemap_blocked"
+	// IssueImageAlt is a record image without alternative text that is
+	// not marked decorative (D-85), from the content descriptors.
+	IssueImageAlt = "image_alt"
+	// IssueH1InContent is an H1 in the body of a record whose page renders
+	// the title as the only H1 (descriptor TopHeading 2, D-50; Journal's
+	// H1 setting on).
+	IssueH1InContent = "h1_in_content"
 )
 
 // The severities an issue may name.
@@ -92,7 +100,92 @@ func (s *Service) Issues(ctx context.Context) ([]Issue, error) {
 		data.listed = append(data.listed, address)
 	}
 	sort.Strings(data.listed)
-	return s.issuesOf(ctx, data, s.canonicalProblem)
+	out, err := s.issuesOf(ctx, data, s.canonicalProblem)
+	if err != nil {
+		return nil, err
+	}
+	content, err := s.ContentIssues(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return append(out, content...), nil
+}
+
+// contentIssuesPage is the page size of the content walk.
+const contentIssuesPage = 200
+
+// ContentIssues are the CMS-data checks on the content descriptors of
+// every published record (D-85, D-50): image_alt for images with an empty
+// alt that are not decorative, and h1_in_content for an H1 in the body of
+// a record whose descriptor sets TopHeading 2 (off when the type sets no
+// rule, as Journal does with its H1 setting off). Each names the record
+// type's fitting tool (ContentDescriptor.Tools: image_alt or headings,
+// else edit); "" when the type names none.
+func (s *Service) ContentIssues(ctx context.Context) ([]Issue, error) {
+	reg := s.Registry()
+	if reg == nil {
+		return nil, nil
+	}
+	var out []Issue
+	for _, typ := range reg.ContentTypes() {
+		if typ.Content == nil || typ.Content.Records == nil {
+			continue
+		}
+		tool := func(ops ...string) string {
+			for _, op := range ops {
+				if t := strings.TrimSpace(typ.Content.Tools[op]); t != "" {
+					return t
+				}
+			}
+			return ""
+		}
+		after := ""
+		for {
+			page, err := reg.Records(ctx, typ.Key, after, contentIssuesPage, s.UnprefixedLocale())
+			if err != nil {
+				return nil, err
+			}
+			for _, rec := range page.Records {
+				if !rec.Published {
+					continue
+				}
+				for _, l := range rec.Locales {
+					if strings.TrimSpace(l.URL) == "" {
+						continue
+					}
+					var missing []string
+					for _, img := range l.Images {
+						if !img.Decorative && strings.TrimSpace(img.Alt) == "" && img.URL != "" {
+							missing = append(missing, img.URL)
+						}
+					}
+					if len(missing) > 0 {
+						out = append(out, Issue{Kind: IssueImageAlt, URL: l.URL, Locale: l.Locale, Tool: tool(pact.ContentToolImageAlt, pact.ContentToolEdit), Details: map[string]any{
+							"count": len(missing), "images": missing, "type": typ.Key, "id": rec.ID,
+						}})
+					}
+					if rec.TopHeading == 2 {
+						var h1 []string
+						for _, h := range l.Headings {
+							if h.Level == 1 {
+								h1 = append(h1, h.Text)
+							}
+						}
+						if len(h1) > 0 {
+							out = append(out, Issue{Kind: IssueH1InContent, URL: l.URL, Locale: l.Locale, Tool: tool(pact.ContentToolHeadings, pact.ContentToolEdit), Details: map[string]any{
+								"count": len(h1), "h1": h1, "type": typ.Key, "id": rec.ID,
+							}})
+						}
+					}
+				}
+			}
+			if page.Next == "" || page.Next == after || len(page.Records) == 0 {
+				break
+			}
+			after = page.Next
+		}
+	}
+	return out, nil
 }
 
 // issueData is what the issue report reads from the database: the SEO