Feat/add igdb rawg providers

[m24ih]

Description

This PR integrates IGDB and RAWG APIs into the plugin, allowing users to search for games using these services. It also includes several fixes and improvements.

Changes

• New APIs: Added support for IGDB and RAWG.
• Settings: Added configuration fields for IGDB (Client ID, Client Secret) and RAWG (API Key).
• Bug Fix (RAWG): Fixed an issue where RAWG release dates were ignoring the user's preferred date format.

Testing

• IGDB: Tested searching for the game "Hytale". Note: Metadata and cover art fetching verified.
• RAWG: Added the implementation but could not verify live search due to sign-up issues on the platform. The code logic for date formatting has been unit-verified.

How to use

Setting up IGDB

To use the IGDB API, you need to generate a Client ID and Client Secret.

1. Follow the instructions here: https://api-docs.igdb.com/#getting-started
2. Enter the credentials in the plugin settings.

Setting up RAWG

1. Get an API key from https://rawg.io/apidocs
2. Enter the key in the plugin settings.

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This PR was created with mostly 'vibe coding'.

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📸 Screenshots

[tuberbacon]

I don't know if this was already accounted for, but since obsidian version 1.11 a new Keychain settings section was added for storing plugin secrets. Since RAWG uses a secret I thought it may be a useful piece of info.

[m24ih]

Thanks for the note. I am aware of the new Keychain settings introduced in Obsidian 1.11. However, I opted to place these credentials within the plugin's own settings to ensure consistency with how other APIs in the project currently handle their keys. If preferred, I can refactor this to utilize the new secret storage system.