add: project unit list

app/controllers/projects/project_units_controller.rb

@@ -1,4 +1,8 @@
 class Projects::ProjectUnitsController < Projects::BaseController
+  def index 
+    @project_units = @project.project_units
+  end
+
   def create 
     if current_user.admin? ||  @project.owner?(current_user)
       ActiveRecord::Base.transaction do 

app/docs/slate/source/includes/_projects.md

@@ -261,8 +261,46 @@ attachments     |array|附件
 Remember — a happy kitten is an authenticated kitten!
 </aside>
 
-## 更改项目导航
-更改项目导航信息
+## 项目模块信息
+项目模块信息
+
+> 示例:
+
+```shell
+curl -X GET \
+http://localhost:3000/api/yystopf/ceshi/project_units.json
+```
+
+```javascript
+await octokit.request('GET /api/yystopf/ceshi/project_units')
+```
+
+### HTTP 请求
+`GET /api/yystopf/ceshi/project_units`
+
+### 返回字段说明:
+参数  | 类型 | 字段说明
+--------- | ----------- | -----------
+|type          |string|模块名称 |
+
+> 返回的JSON示例:
+
+```json
+[
+    {
+        "type": "code"
+    },
+    {
+        "type": "pulls"
+    },
+    {
+        "type": "issues"
+    }
+]
+```
+
+## 更改项目模块展示
+更改项目模块展示
 
 > 示例:
 

app/views/projects/project_units/index.json.jbuilder

@@ -0,0 +1,3 @@
+json.array! @project_units do |unit|
+  json.type unit.unit_type
+end