feat: custom context

[whilefoo]

This implements custom context type which includes event context and bot config. @pavlovcik

[sweep-ai[bot]]

Apply Sweep Rules to your PR?

• [ ] Apply: Leftover TODOs in the code should be handled.
• [ ] Apply: All new business logic should have corresponding unit tests in the tests/ directory.
• [ ] Apply: Any clearly inefficient or repeated code should be optimized or refactored.