[FEATURE] Ability to /clear the context from hook scripts

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

I'd like to be able to trigger context clearing from a hook script. This will allow me to automatically clear the context before beginning a new task, hopefully reducing the token usage over time.

Proposed Solution

Grant hook scripts the ability to invoke arbitrary slash commands

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

Performance and speed

Use Case Example

_No response_

Additional Context

_No response_