[FEATURE] Compact only first half of the chat

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

Sometimes a session drifts from its original goal and when approaching the context limit I would like to be able to /compact only the first half of the chat, not all of it, to avoid losing the recent useful context

Proposed Solution

Sometimes a session drifts from its original goal and when approaching the context limit I would like to be able to /compact only the first half of the chat, not all of it, to avoid losing the recent useful context

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

_No response_