Filter user-visible payment methods to only include supported
providers and fail fast when a payment record or plugin cannot be
resolved.
This prevents invalid payment options from being returned by the
API and avoids constructing an undefined fallback payment class.
- Implement Workerman-based `xboard:ws-server` for real-time node synchronization.
- Support custom routes, outbounds, and certificate configurations via JSON.
- Optimize scheduled tasks with `lazyById` to minimize memory footprint.
- Enhance reactivity using Observers for `Plan`, `Server`, and `ServerRoute`.
- Expand protocol support for `httpupgrade`, `h2`, and `mieru`.
yinjianm