feat(useStrapiGraphQL): support for imported graphql files

[doseofted]

Types of changes

• Bug fix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Description

Adds support for queries that are imported from a file. For instance, if someone used @rollup/plugin-graphql with Vite to import a GraphQL file, the imported file would be a DocumentNode and not the expected query by the Nuxt/Strapi module today. This feature adds support for those imported queries directly in the module without the need to transform the query first, like so:

<script setup lang="ts">
import query from "~/queries/test.gql"

const given = await useStrapiGraphQL(query, { sort: ['createdAt:asc'] })
</script>

Since variables are defined on the query and can't be passed directly when using a file, an optional variables argument is added to the useStrapiGraphQL composable so that those arguments can be passed.

This change relies on #248 (a fix for missing header on request). It also adds a dependency of "graphql" for conversion of given graphql document.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes (if not applicable, please state why)