更改：疑修param为index以及新增统计标签下合并请求数量

app/views/api/v1/issues/index.json.jbuilder

@@ -2,6 +2,7 @@ json.total_issues_count @total_issues_count
 json.opened_count @opened_issues_count
 json.closed_count @closed_issues_count
 json.total_count @issues.total_count 
+json.has_created_issues @project.issues.size > 0
 json.issues @issues.each do |issue| 
   json.partial! "simple_detail", locals: {issue: issue}
 end

app/views/api/v1/issues/issue_tags/_detail.json.jbuilder

@@ -1,6 +1,6 @@
 json.(tag,:id, :name, :description, :color)
-json.issues_count tag.issue_issues.size 
-json.pull_requests_count tag.pull_request_issues.size
+json.issues_count tag.issues_count
+json.pull_requests_count tag.pull_requests_count
 json.project do 
   if tag.project.present? 
     json.partial! "api/v1/projects/simple_detail", project: tag.project