Show image size on view page (#25884)

This simply shows the Image size on the view page. This is useful, if
you search a image with a specific size.


![grafik](https://github.com/go-gitea/gitea/assets/15185051/9868e361-1c2e-447f-b824-70aa28bafcbc)

templates/repo/file_info.tmpl

@@ -30,4 +30,9 @@
 			{{.locale.Tr "repo.executable_file"}}
 		</div>
 	{{end}}
+	{{if .ImageSize}}
+		<div class="file-info-entry">
+			{{.ImageSize}}
+		</div>
+	{{end}}
 </div>