[FEATURE] Surface up the session token limit bar in the desktop app

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

Surface up the session token limit information into the main window of the desktop application.

Why: So I can quickly estimate how many more requests I can make in the current session without repeatedly opening Settings -> usage.
Expected workflow: See remaining headroom at a glance while working, without interrupting my flow.
Scope: Session usage only (not weekly).

Proposed Solution

Keep the session token usage limit bar in Settings → Usage, and also show a duplicate always-visible session usage indicator in the desktop app right-hand panel.

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

_No response_