ref(relay): Remove old error processing pipeline

[Dav1dde]

Does not perform any manual cleanup, like:

• Unify playstation code into utils/ (like unreal)
• Combine expand and process unreal phases into a single function (no more double parsing)
• Move switch to utils (like unreal)
• Check for more code which can be moved and deleted

[olksdr]

🚢 it!

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit 29b8b86. Configure here.}