Feature request: Show plan usage allowance in status bar

Feature Request

Problem: I have no visibility into how much of my plan allowance I've consumed until I hit rate limits or manually run /usage. I often don't realise until it's at 90%+ that I'm running low.

Current workaround: Manually typing /usage periodically - easy to forget and breaks flow.

Proposed solution: Add an option to display remaining plan allowance in the status line, showing both total plan usage and current session usage:


Plan: ████████░░ 78% used | Session: .24 (3.2k turns) | Context: ███░░░░░░░ 30% | opus-4-6


Metrics to include:

• Plan usage - percentage of total allowance consumed this billing period (the key one!)
• Session usage - cost/tokens consumed in the current session so far (currently only visible via /cost)
• Both updating in real-time in the status bar

Why this matters:

• Users can pace their work across a billing period instead of hitting limits mid-task with no warning
• Session cost visibility helps users understand which tasks are expensive
• The status line infrastructure already exists - this just needs a new data source

Alternatives considered:

• Having Claude remind users to run /usage periodically - unreliable since Claude can't execute slash commands itself
• A CLAUDE.md instruction to prompt the user - doesn't actually work in practice