feat: editor heading levels, outline, link rel, generic-anchor warning and image naming

- the blogeditor and mlblogeditor types serve headingLevels and
  genericAnchors through RequestOptions, per schema request
- J1: H2 to H4 with a pasted or loaded H1 parsed as H2 while the H1
  setting is on, H1 to H4 while it is off; H5 and H6 still parse
- J2: the outline bar and panel (skipped, empty, link-only, H1 in Source,
  generic link texts), 300 ms after a change, collapsed, read-only
- J3: nofollow/sponsored/ugc checkboxes for absolute http(s) links only,
  and a non-blocking warning for a generic link text
- J4: one form per picked file with the slugged file name, alt required
  unless decorative (alt=""); Insert uploads the renamed file and the
  image is inserted on the upload result
- assets/dist rebuilt

classes/blog_editor.go

@@ -19,6 +19,7 @@ import (
 	"git.golem15.com/golem15/summercms/modules/pact"
 	"gocloud.dev/blob"
 	xhtml "golang.org/x/net/html"
+	"gorm.io/gorm"
 )
 
 // BlogEditorElement is the custom element of the blogeditor and mlblogeditor
@@ -88,31 +89,34 @@ var (
 func BlogEditorTypes(app func() *backpack.App) []pact.FormFieldType {
 	upload := uploadBlogImage(app)
 	decode := decodeBlogHTMLFor(app)
+	options := blogRequestOptions(app)
 	return []pact.FormFieldType{
 		{
-			Name:         "blogeditor",
-			Element:      BlogEditorElement,
-			Scripts:      []string{"assets/dist/blogeditor.js"},
-			Styles:       []string{"assets/dist/blogeditor.css"},
-			Options:      []string{"uploadFolder"},
-			CheckOptions: checkBlogOptions,
-			Decode:       decode,
-			Load:         loadBlogHTML,
-			ListValue:    blogListValue,
-			Upload:       upload,
+			Name:           "blogeditor",
+			Element:        BlogEditorElement,
+			Scripts:        []string{"assets/dist/blogeditor.js"},
+			Styles:         []string{"assets/dist/blogeditor.css"},
+			Options:        []string{"uploadFolder"},
+			CheckOptions:   checkBlogOptions,
+			Decode:         decode,
+			Load:           loadBlogHTML,
+			ListValue:      blogListValue,
+			Upload:         upload,
+			RequestOptions: options,
 		},
 		{
-			Name:         "mlblogeditor",
-			Element:      BlogEditorElement,
-			Translatable: true,
-			Scripts:      []string{"assets/dist/blogeditor.js"},
-			Styles:       []string{"assets/dist/blogeditor.css"},
-			Options:      []string{"htmlColumn", "uploadFolder"},
-			CheckOptions: checkBlogOptions,
-			Decode:       decode,
-			Load:         loadBlogHTML,
-			ListValue:    blogListValue,
-			Upload:       upload,
+			Name:           "mlblogeditor",
+			Element:        BlogEditorElement,
+			Translatable:   true,
+			Scripts:        []string{"assets/dist/blogeditor.js"},
+			Styles:         []string{"assets/dist/blogeditor.css"},
+			Options:        []string{"htmlColumn", "uploadFolder"},
+			CheckOptions:   checkBlogOptions,
+			Decode:         decode,
+			Load:           loadBlogHTML,
+			ListValue:      blogListValue,
+			Upload:         upload,
+			RequestOptions: options,
 		},
 	}
 }
@@ -194,6 +198,25 @@ func h1ConvertedNotice(record any) string {
 	return EditorH1Converted
 }
 
+// blogRequestOptions is the Blog Editor types' RequestOptions (33-01
+// P33-02, UI-SPEC C28): headingLevels, [2, 3, 4] while the H1 setting is on
+// and [1, 2, 3, 4] while it is off (J1), and genericAnchors, the settings'
+// generic link texts (J2, J3). Both are read per schema request, so a
+// changed setting reaches the next form that opens. db may be nil; the
+// defaults then apply. fields.yaml options with the same names win.
+func blogRequestOptions(app func() *backpack.App) func(context.Context, *gorm.DB) (map[string]any, error) {
+	return func(ctx context.Context, db *gorm.DB) (map[string]any, error) {
+		levels := []int{2, 3, 4}
+		if !EffectiveH1ToH2(ctx, db, appConfig(app)) {
+			levels = []int{1, 2, 3, 4}
+		}
+		return map[string]any{
+			"headingLevels":  levels,
+			"genericAnchors": GenericAnchors(ctx, db),
+		}, nil
+	}
+}
+
 // appConfig is the config of the application app answers, nil when there
 // is none.
 func appConfig(app func() *backpack.App) *compass.Config {