Add round-robin/random proxy pool rotation for no-auth free providers
(e.g. OpenCode Free) to distribute load across all active pools and
avoid per-IP rate limits. Rotation strategy is selectable per provider
in NoAuthProxyCard and persisted to settings.providerStrategies.
Bootstrap → JWT → chat flow with auto-retry. Inject the MiMoCode
system marker required to pass the upstream 403 anti-abuse gate,
derive JWT expiry from the exp claim, and use a stable per-machine
fingerprint as the bootstrap client.
Co-authored-by: Cursor <cursoragent@cursor.com>