release: v0.51.495 — guard EventSource.close() to suppress ERR_ABORTED noise (#4422)

Co-authored-by: bergeouss <bergeouss@users.noreply.github.com>

Closes #4422

CHANGELOG.md

@@ -3,6 +3,12 @@
 
 ## [Unreleased]
 
+## [v0.51.495] — 2026-06-18 — Release RE (suppress ERR_ABORTED console noise on SSE close)
+
+### Fixed
+
+- **Closing an SSE/EventSource stream that has already closed no longer logs `ERR_ABORTED` console noise (#4313).** Every `EventSource.close()` teardown site (chat stream, session stream, approval/clarify/kanban/gateway SSE, terminal) now checks `readyState !== 2` (not already CLOSED) before calling `close()`, wrapped in a `try/catch`. Functionally identical — it only avoids the redundant `close()` on an already-aborted source that produced the spurious console errors. Thanks @bergeouss.
+
 ## [v0.51.494] — 2026-06-18 — Release RD (TLS-aware launcher health probes)
 
 ### Fixed