Fix TwitchLogin + Example

[xxxpabloxxx]

Description

Fixed a crash caused by invalid persistent cookie parsing and resolved an issue where the user_id could not be retrieved from the Twitch API.

Specific changes:

• Added try-except block in get_user_id to gracefully handle malformed persistent cookies.
• Updated Authorization header to use OAuth prefix instead of Bearer to match Twitch GQL API requirements.
• Added Client-Version header to __set_user_id requests.
• Changed cookie parsing warning to debug level to reduce log noise.

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality not to work as expected)

How Has This Been Tested?

Ran the bot locally and verified that:

1. The ValueError trace is no longer raised on startup.
2. The bot attempts to fetch user_id via API if the cookie is invalid.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented on my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (README.md)
• My changes generate no new warnings
• Any dependent changes have been updated in requirements.txt