修改 /api/factories 的回傳格式，一次回傳 factories, documents 與 report_records 減少前端需要的 query 次數

[Swind]

/api/statistics/factories

參數有

• townname
• source
• display_status
• level

前三個是之前就有的就不多解釋，最主要就是多了一個 level
level 可以接受的值是 city 與 town
e.g.

/api/statistics/factories
回傳全台灣的資料，但是不會有縣市與鄉鎮市區的資料

{
  "factories": 53914,
  "documents": 200,
  "report_records": 0
}

/api/statistics/factories?level=city
回傳全台灣與縣市資料

{
  "factories": 53914,
  "documents": 200,
  "report_records": 0,
  "cities": {
    "基隆市": {
      "factories": 0,
      "documents": 0,
      "report_records": 0
    },
    "臺北市": {
      "factories": 0,
      "documents": 0,
      "report_records": 0
    },
    ...
}

/api/statistics/factories?level=town
回傳全台灣, 縣市與鄉鎮市區的資料

{
  "factories": 53914,
  "documents": 200,
  "report_records": 0,
  "cities": {
    "基隆市": {
      "factories": 0,
      "documents": 0,
      "report_records": 0,
      "towns": {
        "仁愛區": {
          "factories": 0,
          "documents": 0,
          "report_records": 0
        },
     ....
} 

如果跟 townname 結合的話

/api/statistics/factories?townname=臺南市&level=town

{
  "factories": 53914,
  "documents": 200,
  "report_records": 0,
  "cities": {
    "臺南市": {
      "factories": 5732,
      "documents": 100,
      "report_records": 0,
      "towns": {
        "中西區": {
          "factories": 0,
          "documents": 0,
          "report_records": 0
        },
....

/api/statistics/factories?townname=臺南市善化區

{
  "factories": 53914,
  "documents": 200,
  "report_records": 0,
  "cities": {
    "臺南市": {
      "factories": 5732,
      "documents": 100,
      "report_records": 0,
      "towns": {
        "善化區": {
          "factories": 238,
          "documents": 0,
          "report_records": 0
        }
      }
    }
  }
}

/api/statistics/factories?townname=臺南市

{
  "factories": 53914,
  "documents": 200,
  "report_records": 0,
  "cities": {
    "臺南市": {
      "factories": 5732,
      "documents": 100,
      "report_records": 0
    }
  }
}

[stegben]

lgtm