[FEATURE] display context length remaining before compaction

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

currently compaction just completely breaks all the workflow, - after it happens it tends to be easier to start a new session and re-explain where we left off.

so every request fills like russian rulette, - constant wondering of whether I should try to get to correct state asap to continue in a new session, or risk getting a random compaction

having an indicator (like one for getting close to exceeding request limit) here would be great

Priority

High - Significant impact on productivity

Feature Category

Interactive mode (TUI)