Add fetch interceptors and custom parameters

[ReS4]

This PR provides a set of custom attributes for fetch requests including request and response interceptors.

<script setup>
  const request = "http://vuefinder-php.test"
  
  // Or ...
  const request = {
    // ----- CHANGE ME! -----
    // [REQUIRED] Url for development server endpoint
    baseUrl: "http://vuefinder-php.test",
    // ----- CHANGE ME! -----

    // Additional headers & params & body
    headers: { "X-ADDITIONAL-HEADER": 'yes' },
    params: { additionalParam1: 'yes' },
    body: { additionalBody1: ['yes'] },

    // And/or transform request callback
    transformRequest: req => {
      if (req.method === 'get') {
        req.params.vf = "1"
      }
      return req;
    },

    // XSRF Token header name
    xsrfHeaderName: "X-CSRF-TOKEN",

    // Custom fetch parameters
    fetchParams: {
      'credentials': 'include',
      'mode': 'cors'
    },

    fetchRequestInterceptor: (req: any) => {
      console.log(req)
      return req;
    },

    fetchResponseInterceptor: async (response: any) => {
      console.log(response)
      return response;
    },
  }
</script>

[n1crack]

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