[Feature Request] Add configurable polling interval for statusLine command refresh

Bug Description
Feature request: add a statusLine.refreshIntervalMs (or pollMs) option to settings.json so the statusLine command re-runs on a timer in addition to
user-triggered events (prompt submit, tool finish, focus).

Use case: my statusLine reads from a local cache file that an external process updates (in my case, a Chrome extension scrapes claude.ai/settings/usage and writes
the spend figure to disk every ~60s, so the line shows my real cap usage). The cache is always fresh, but Claude Code never re-invokes the script while a window is
idle, so other open windows display stale values until I focus them or type something.

Today's behavior: statusLine is purely event-driven — there's no documented way to force a refresh from outside, and no refreshIntervalMs knob.

Proposed shape:
{
"statusLine": {
"type": "command",
"command": "bash /path/to/script.sh",
"refreshIntervalMs": 30000
}
}
Default unset = current event-only behavior. Min value clamped to something sensible (e.g., 5000) so users can't accidentally burn cycles.

Why it's broadly useful: any statusLine backed by externally-updated state benefits — CI/build status, git fetch indicators, AWS session expiry, oncall status,
token budget meters. The pattern of "shell out to read a cached value" is already idiomatic; this just lets it stay live across idle windows.

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.123
• Feedback ID: 8b7e8edc-1b2c-4f7d-b5ab-652e755fd68d

Errors

[{"error":"Error: Request was aborted.\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:50:3448)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-11T21:43:40.997Z"}]