[ENHANCEMENT] [pixles-api] Finalize GraphQL schema

[justin13888]

Feature Description

Assuming pixles-swift client implementation is finalized, we want to ensure the GraphQL implementation pixles-api has all necessary queries, mutations, subscriptions for all app functionality.

Target Component

• pixles-api
• pixles-core-kotlin
• pixles-desktop
• pixles-docs
• pixles-media
• pixles-swift
• pixles-web
• Other: _____________________