Implement nickname filter for avatar field

[Atralupus]

Currently, avatars can only be queried using their address. However, in the game, most users rely on nicknames, and it would be more intuitive for users to search for avatars by nickname through Mimir.

Here’s how the data is stored in the database:

Desired Query Example:

query {
  avatar(nickname: "atralupus") {
    address
    agentAddress
  }
}

Steps to Implement:

1. Update AvatarRepository
   Add a new method GetByNicknameAsync to search by nickname. Use the following filter:

   var filter = Builders<AvatarDocument>.Filter.Eq("Object.Name", nickname);

2. Update Query
   Modify the GraphQL query to accept nickname as a parameter.

   Example:

   public async Task<AvatarState> GetAvatarAsync(
       Address? address,
       string? nickname,
       [Service] AvatarRepository repo
   )
   {
       if (address is not null)
       {
           return (await repo.GetByAddressAsync(address.Value)).Object;
       }
       else if (!string.IsNullOrEmpty(nickname))
       {
           return (await repo.GetByNicknameAsync(nickname)).Object;
       }
       else
       {
           throw new ArgumentException("Either address or nickname must be provided.");
       }
   }

To set up the database locally, follow the steps below:

1. Refer to the CONTRIBUTING.md Document:
   Check the CONTRIBUTING.md file in the Mimir repository for detailed setup instructions.

2. Download Data:
   Download the sample data from this link.

3. Restore or Import Data:
   Once downloaded, ensure the avatar collection is created in your MongoDB instance and populate it with the provided data. You can use tools like a MongoDB GUI (e.g., Compass) to import the data.

[gagan-bhullar-tech]

@Atralupus can you please assign it to me

[Atralupus]

@Atralupus can you please assign it to me

@gagan-bhullar-tech I assigned you to this issue!

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[Atralupus]

You can set up the database locally in a similar way to the comment in this issue.

I've prepared 100 sample avatars and uploaded them here. Feel free to use them if needed!
Download link