Add method to get the raw index information

[curquiza]

trafficstars

⚠️ This issue is generated, it means the examples and the namings do not necessarily correspond to the language of this repository. Also, if you are a maintainer, feel free to add any clarification and instruction about this issue.

Sorry if this is already partially/completely implemented, feel free to let me know about the state of this issue in the repo.

Related to https://github.com/meilisearch/integration-guides/issues/120

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This SDK provides a method to get an index (getIndex) and this method returns an instance of Index. Some users want to get the raw version of the index, I mean the exact JSON response returned by the MeiliSearch server, not an instance.

Some SDKs already provide a way to get this raw index information but this is not convenient, example in PHP:

$client->index('movies')->fetchRawInfo();

We need to add the getRawIndex method, accessible from the Client instance, to make it more convient.

Prototype:

getRawIndex(string indexUID) -> object/struct/dict of the MeiliSearch response

Ex in PHP:

$client->getRawIndex('movies');

TODO:

• [ ] Add getRawIndex() method to the Client instance without duplicating the code (if fetchRawInfo() already exists for example)
• [ ] Add tests