markup/goldmark: Add removeSurroundingParagraph for Markdown images

* Removes any surrounding paragraph nodes
* And transfers any attributes from the surrounding paragraph down to the image node
* Adds IsBlock and Ordinal (zero based) field to the image context passed to the image render hooks

IsBlock is set to true if `wrapStandAloneImageWithinParagraph = false` and  the image's parent node has only one child.

Closes #8362
Fixes #10492
Fixes #10494
Fixes #10501

markup/goldmark/goldmark_config/config.go

@@ -36,8 +36,9 @@ var Default = Config{
 		Unsafe: false,
 	},
 	Parser: Parser{
-		AutoHeadingID:     true,
-		AutoHeadingIDType: AutoHeadingIDTypeGitHub,
+		AutoHeadingID:                      true,
+		AutoHeadingIDType:                  AutoHeadingIDTypeGitHub,
+		WrapStandAloneImageWithinParagraph: true,
 		Attribute: ParserAttribute{
 			Title: true,
 			Block: false,
@@ -88,6 +89,9 @@ type Parser struct {
 
 	// Enables custom attributes.
 	Attribute ParserAttribute
+
+	// Whether to wrap stand-alone images within a paragraph or not.
+	WrapStandAloneImageWithinParagraph bool
 }
 
 type ParserAttribute struct {