map/world: SessionEndConfirm hardcodes error_code=1 — world-server logs "error ending session" on every disconnect and skips confirm-side cleanup

[swstegall]

Symptom

world-server logs ERROR error ending session session=N on every disconnect (live logs 2026-07-04, 7/7 disconnects).

Mechanism

The error is self-inflicted: map-server's session-end reply hardcodes the error code to 1 —

map-server/src/processor.rs:630:

let reply = tx::build_session_end(session_id, 1, 0);

world-server's confirm handler sees error != 0, takes its error branch, and skips confirm-side cleanup — which also leaves the cross-zone handoff protocol dead on that path. A proper builder already exists: build_session_end_confirm (map-server/src/packets/send/world_packets.rs:49) with error 0 for the success case.

Impact

• Permanent log noise that masks real teardown failures (this hid the actor-leak symptoms during the Ubuntu investigation).
• world-server's confirm-side session cleanup never runs, contributing to stale session/actor state (see the ghost-player issue).

Suggested fix

Send error 0 on successful teardown (reserve non-zero for genuine failures), and audit what world-server's confirm-side cleanup should be doing once it finally runs.

Found during the Ubuntu opening-quest root-cause investigation (branch feature/ubuntu, commit f6897e5).