feat: hooks - automatically trigger agent actions (incl. skill + tool calls) on specific user actions or other agent actions

[oamazonasgabriel]

Feature name: Hooks

User Interface for general hook configurations.

Main Examples:

1. Run a test coverage validation before every commit, against a given threshold
2. Build and Run unit tests on every commit
3. Run e2e tests for the related features before every push

If the Hook was triggered by the human or the agent, it should work the same way.