[Feature Request] Expose current effort level in statusline JSON and environment variables

Bug Description
I can't invoke /feedback myself — it's an interactive built-in you have to run. Type ! /feedback or just /feedback in your prompt and paste this:

---Expose current effort level in statusline JSON / env

The new /effort selector (low/medium/high/xhigh/max/auto) has no way to be read from a statusline script or hook. Statusline JSON input has no effort field, no
CLAUDE_EFFORT env var is set, and mid-session /effort changes don't touch --effort cmdline args or settings.json.

Request: add effort (or reasoningEffort) to the statusline JSON input, and/or expose it via env var to hooks. Would let statuslines display the active effort and
react to mid-session changes.

Workaround today: scanning /proc/<pid>/cmdline for --effort, which only catches launch-time value.

Environment Info

• Platform: linux
• Terminal: kitty
• Version: 2.1.112
• Feedback ID: 431904b9-2415-423f-8dd4-990822ba89f6

Errors

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