[FEATURE] persistent context/cost indicator in the status bar like in OpenCode, or custom bash prompt (PS0/PS1)

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

Hi, I love /context command, but I would like to have a persistent simple % info on my model context usage in a session to monitor it, whether I want to restart it, or maybe I am giving it too much context at the initial prep input etc.

Proposed Solution

OpenCode has a very simple solution of showing % usage all the time with something like:

x tokens
x% used
$0.00 spend

I understand not everyone may want it enabled by default, but having an option to configure your status bar like opencode or like bash prompt wiht PS0/PS1 is probably something a lot of people would want.

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_