An idle, suspended, or manually refreshed widget presented its last
measurement as current until the periodic timer fired again. Opening the
popup is the moment the user asks for the number, so make that refresh the
default instead of an opt-in.

PopupRefreshPolicy already bounds the cost: only quotas older than the
refresh interval are fetched, in-flight and scheduled runs are skipped, and
failed attempts keep the same cooldown, so reopening the popup cannot start
a request per opening. Local cost history is still not scanned.

The refresh-on-open smoke scenario asserted that the default did not
refresh; it now disables the setting explicitly to cover the opt-out and
keeps the fresh/stale/reopen sequence unchanged.

Documentation: usage guide default table and option description, README
feature list and new-widget defaults, CHANGELOG under Unreleased. TODO is
unaffected; the dated settings-experience audit keeps its original finding.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QvM85i7ZFMLEAvUAz742vq