Handle fatal connection attempt errors

[jackyzha0]

Why

River exposes isFatalConnectionError so callers can stop retrying connection failures that are permanent. That hook was only honored after a connection had been established, so fatal failures during the initial connection attempt still retried until the retry budget or session grace behavior kicked in.

This is needed for pid2 auth failures where the target repl is gone: callers can classify that as fatal and avoid the noisy retry loop.

What changed

• Honor isFatalConnectionError in the initial onConnectionFailed path.
• Disable reconnects and delete the unhealthy pending session when the initial connection error is fatal.
• Add a regression test covering fatal initial connection failures.
• Bump @replit/river to 0.219.0.

Versioning

• Breaking protocol change
• Breaking ts/js API change

Test plan

• direnv exec . npm run check
• direnv exec . npm exec -- vitest run