Add template_encode in output for custom templates

[ehsandeep]

Please describe your feature request:

id: basic-example

info:
  name: Test HTTP Template
  author: pdteam
  severity: info

http:
  - method: GET
    path:
      - "{{BaseURL}}"
    matchers:
      - type: word
        words:
          - "This is test matcher text"
        negative: true

echo https://scanme.sh | ./nuclei -t test.yaml -j | jq .

{
  "template-id": "basic-example",
  "template-path": "/Users/geekboy/Github/nuclei/v2/test.yaml",
  "template_encoded": "aWQ6IGJhc2ljLWV4YW1wbGUKCmluZm86CiAgbmFtZTogVGVzdCBIVFRQIFRlbXBsYXRlCiAgYXV0aG9yOiBwZHRlYW0KICBzZXZlcml0eTogaW5mbwoKaHR0cDoKICAtIG1ldGhvZDogR0VUCiAgICBwYXRoOgogICAgICAtICJ7e0Jhc2VVUkx9fSIKICAgIG1hdGNoZXJzOgogICAgICAtIHR5cGU6IHdvcmQKICAgICAgICB3b3JkczoKICAgICAgICAgIC0gIlRoaXMgaXMgdGVzdCBtYXRjaGVyIHRleHQiCiAgICAgICAgbmVnYXRpdmU6IHRydWU="
  "info": {
    "name": "Test HTTP Template",
    "author": [
      "pdteam"
    ],
    "tags": null,
    "severity": "info"
  },
  "type": "http",
  "host": "https://scanme.sh",
  "matched-at": "https://scanme.sh",
  "request": "GET / HTTP/1.1\r\nHost: scanme.sh\r\nUser-Agent: Mozilla/5.0 (Windows NT 10.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.36\r\nConnection: close\r\nAccept: */*\r\nAccept-Language: en\r\nAccept-Encoding: gzip\r\n\r\n",
  "response": "HTTP/1.1 200 OK\r\nConnection: close\r\nContent-Length: 2\r\nContent-Type: text/plain; charset=utf-8\r\nDate: Sun, 08 Oct 2023 10:28:45 GMT\r\n\r\nok",
  "ip": "128.199.158.128",
  "timestamp": "2023-10-08T15:58:45.615485+05:30",
  "curl-command": "curl -X 'GET' -H 'Accept: */*' -H 'Accept-Language: en' -H 'User-Agent: Mozilla/5.0 (Windows NT 10.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.36' 'https://scanme.sh'",
  "matcher-status": true
}

Also optionally:

   -ot, -omit-template  omit encoded template in the JSON, JSONL output

Describe the use case of this feature:

Public nuclei templates contain template-url; instead, in custom templates, no information is available, adding template_encoded will make the nuclei output self-sufficient, containing all the information for review and replication.

Anything else:

URL is handled using below method for public templates:

// TemplatePathURL returns the Path and URL for the provided template
func TemplatePathURL(fullPath, templateId string) (string, string) {
	var templateDirectory string
	configData := config.DefaultConfig
	if configData.TemplatesDirectory != "" && strings.HasPrefix(fullPath, configData.TemplatesDirectory) {
		templateDirectory = configData.TemplatesDirectory
	} else {
		return "", ""
	}

	finalPath := strings.TrimPrefix(strings.TrimPrefix(fullPath, templateDirectory), "/")
	templateURL := TemplatesRepoURL + templateId
	return finalPath, templateURL
}

Note:

• Max length for template size needs to be defined.
• If the template length exceeds the max, it will be omitted from the result.